Monday, June 17, 2019

Number of the day: 245158254

Properties of the number 245158254:

245158254 = 2 × 32 × 11 × 19 × 65167 is the 231729379th composite number and is not squarefree.
245158254 has 5 distinct prime factors, 48 divisors, 29 antidivisors and 70379280 totatives.
245158254 has a triangular digit sum 36 in base 10.
245158254 = 2383 + 2853 + 5933 is the sum of 3 positive cubes in 1 way.
245158254 is the difference of 2 positive pentagonal numbers in 4 ways.
245158254 = 502 + 2772 + 156552 is the sum of 3 positive squares.
2451582542 is the sum of 3 positive squares.
245158254 is a proper divisor of 68321722 - 1.
245158254 = '24515' + '8254' is the concatenation of 2 semiprime numbers.

Sunday, June 16, 2019

Number of the day: 5328

Properties of the number 5328:

5328 = 24 × 32 × 37 is the 4622th composite number and is not squarefree.
5328 has 3 distinct prime factors, 30 divisors, 7 antidivisors and 1728 totatives.
5328 has an oblong digit product 240 in base 10.
5328 is the difference of 2 nonnegative squares in 9 ways.
5328 is the sum of 2 positive triangular numbers.
5328 is the difference of 2 positive pentagonal numbers in 1 way.
5328 = 122 + 722 is the sum of 2 positive squares in 1 way.
5328 = 162 + 442 + 562 is the sum of 3 positive squares.
53282 = 17282 + 50402 is the sum of 2 positive squares in 1 way.
53282 is the sum of 3 positive squares.
5328 is a proper divisor of 732 - 1.
5328 is palindromic in (at least) the following bases: 11, and 73.
5328 in base 6 = 40400 and consists of only the digits '0' and '4'.
5328 in base 11 = 4004 and consists of only the digits '0' and '4'.
5328 in base 17 = 1177 and consists of only the digits '1' and '7'.
5328 in base 19 = ee8 and consists of only the digits '8' and 'e'.
5328 in base 36 = 440 and consists of only the digits '0' and '4'.
5328 in base 51 = 22O and consists of only the digits '2' and 'O'.

The number 5328 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A033996: 8 times triangular numbers: a(n) = 4*n*(n+1).
A084920: a(n) = (prime(n)-1)*(prime(n)+1).
A106302: Period of the Fibonacci 3-step sequence A000073 mod prime(n).
A173116: a(n) = sinh(2*arcsinh(n))^2 = 4*n^2*(n^2 + 1).
A179669: Products of form p^4*q^2*r where p, q and r are three distinct primes.
A236278: T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median unequal to the lower median in every 2X2 subblock
A247726: T(n,k)=Number of length n+3 0..k arrays with no disjoint pairs in any consecutive four terms having the same sum
A248925: Triangle in which row n consists of the coefficients in Sum_{m=0..n} x^m * Product_{k=m+1..n} (1-k*x), as read by rows.
A257368: Numbers n such that the decimal expansions of both n and n^2 have 2 as smallest digit and 8 as largest digit.
A317707: Number of powerful rooted trees with n nodes.

Thursday, June 13, 2019

Number of the day: 286345

John Forbes Nash, Jr. was born on this day 91 years ago.

Properties of the number 286345:

286345 is a cyclic number.
286345 = 5 × 57269 is semiprime and squarefree.
286345 has 2 distinct prime factors, 4 divisors, 11 antidivisors and 229072 totatives.
286345 has a triangular digit sum 28 in base 10.
Reversing the decimal digits of 286345 results in an emirpimes.
286345 = 1431732 - 1431722 = 286372 - 286322 is the difference of 2 nonnegative squares in 2 ways.
286345 is the sum of 2 positive triangular numbers.
286345 is the difference of 2 positive pentagonal numbers in 2 ways.
286345 = 2882 + 4512 = 1882 + 5012 is the sum of 2 positive squares in 2 ways.
286345 = 442 + 752 + 5282 is the sum of 3 positive squares.
2863452 = 1883762 + 2156572 = 1718072 + 2290762 = 1204572 + 2597762 = 595002 + 2800952 is the sum of 2 positive squares in 4 ways.
2863452 is the sum of 3 positive squares.
286345 is a proper divisor of 1429278 - 1.
286345 = '286' + '345' is the concatenation of 2 sphenic numbers.
286345 is an emirpimes in (at least) the following bases: 2, 10, 22, 25, 28, 29, 37, 38, 41, 43, 48, 52, 55, 57, 60, 63, 65, 67, 71, 72, 73, 77, 82, 91, 92, 93, and 99.

Wednesday, June 12, 2019

Number of the day: 712398

Vladimir Igorevich Arnold was born on this day 82 years ago.

Properties of the number 712398:

712398 = 2 × 3 × 37 × 3209 is the 654913th composite number and is squarefree.
712398 has 4 distinct prime factors, 16 divisors, 15 antidivisors and 230976 totatives.
712398 has a sphenic digit sum 30 in base 10.
712398 has an oblong digit sum 30 in base 10.
712398 is the sum of 2 positive triangular numbers.
712398 is the difference of 2 positive pentagonal numbers in 4 ways.
712398 = 172 + 1222 + 8352 is the sum of 3 positive squares.
7123982 = 4706402 + 5347982 = 3532502 + 6186482 = 2717522 + 6585302 = 2310482 + 6738902 is the sum of 2 positive squares in 4 ways.
7123982 is the sum of 3 positive squares.
712398 is a proper divisor of 102172 - 1.
712398 is palindromic in (at least) base -96.

Tuesday, June 11, 2019

Number of the day: 771577455

Properties of the number 771577455:

771577455 = 3 × 5 × 11 × 4676227 is the 731819308th composite number and is squarefree.
771577455 has 4 distinct prime factors, 16 divisors, 19 antidivisors and 374098080 totatives.
Reversing the decimal digits of 771577455 results in a sphenic number.
771577455 = 3857887282 - 3857887272 = 1285962442 - 1285962412 = 771577482 - 771577432 = 350717082 - 350716972 = 257192562 - 257192412 = 116905842 - 116905512 = 70143682 - 70143132 = 23381962 - 23380312 is the difference of 2 nonnegative squares in 8 ways.
771577455 is the difference of 2 positive pentagonal numbers in 4 ways.
771577455 is not the sum of 3 positive squares.
7715774552 = 4629464732 + 6172619642 is the sum of 2 positive squares in 1 way.
7715774552 is the sum of 3 positive squares.
771577455 is a proper divisor of 199150846 - 1.

Monday, June 10, 2019

Number of the day: 264666435

Properties of the number 264666435:

264666435 = 3 × 5 × 11 × 223 × 7193 is the 250229848th composite number and is squarefree.
264666435 has 5 distinct prime factors, 32 divisors, 35 antidivisors and 127729920 totatives.
264666435 has a sphenic digit sum 42 in base 10.
264666435 has an oblong digit sum 42 in base 10.
264666435 is the difference of 2 nonnegative squares in 16 ways.
264666435 is the difference of 2 positive pentagonal numbers in 7 ways.
264666435 = 4272 + 8452 + 162412 is the sum of 3 positive squares.
2646664352 = 1012892762 + 2445174932 = 656790752 + 2563875602 = 1657026032 + 2063757962 = 1587998612 + 2117331482 is the sum of 2 positive squares in 4 ways.
2646664352 is the sum of 3 positive squares.
264666435 is a proper divisor of 967444 - 1.
264666435 = '264666' + '435' is the concatenation of 2 sphenic numbers.

Sunday, June 9, 2019

Number of the day: 791708

John Edensor Littlewood was born on this day 134 years ago.

Properties of the number 791708:

791708 = 22 × 197927 is the 728373th composite number and is not squarefree.
791708 has 2 distinct prime factors, 6 divisors, 33 antidivisors and 395852 totatives.
Reversing the decimal digits of 791708 results in a prime.
791708 = 1979282 - 1979262 is the difference of 2 nonnegative squares in 1 way.
791708 is the difference of 2 positive pentagonal numbers in 1 way.
791708 is not the sum of 3 positive squares.
7917082 is the sum of 3 positive squares.
791708 is a proper divisor of 1798963 - 1.
791708 is palindromic in (at least) base -93.

Saturday, June 8, 2019

Number of the day: 80997

Properties of the number 80997:

80997 = 3 × 72 × 19 × 29 is the 73071th composite number and is not squarefree.
80997 has 4 distinct prime factors, 24 divisors, 35 antidivisors and 42336 totatives.
80997 has a semiprime digit sum 33 in base 10.
80997 is the difference of 2 nonnegative squares in 12 ways.
80997 is the sum of 2 positive triangular numbers.
80997 is the difference of 2 positive pentagonal numbers in 4 ways.
80997 = 172 + 822 + 2722 is the sum of 3 positive squares.
809972 = 558602 + 586532 is the sum of 2 positive squares in 1 way.
809972 is the sum of 3 positive squares.
80997 is a proper divisor of 5216 - 1.
80997 = '809' + '97' is the concatenation of 2 prime numbers.
80997 in base 34 = 2229 and consists of only the digits '2' and '9'.

Friday, June 7, 2019

Number of the day: 763132

Properties of the number 763132:

763132 = 22 × 190783 is the 701917th composite number and is not squarefree.
763132 has 2 distinct prime factors, 6 divisors, 23 antidivisors and 381564 totatives.
763132 has a semiprime digit sum 22 in base 10.
763132 has an oblong digit product 756 in base 10.
Reversing the decimal digits of 763132 results in a prime.
763132 = 1907842 - 1907822 is the difference of 2 nonnegative squares in 1 way.
763132 is the sum of 2 positive triangular numbers.
763132 is the difference of 2 positive pentagonal numbers in 1 way.
763132 is not the sum of 3 positive squares.
7631322 is the sum of 3 positive squares.
763132 is a proper divisor of 6013533 - 1.

Thursday, June 6, 2019

Number of the day: 2307484

Aleksandr Mikhailovich Lyapunov was born on this day 162 years ago.

Properties of the number 2307484:

2307484 = 22 × 733 × 787 is the 2137465th composite number and is not squarefree.
2307484 has 3 distinct prime factors, 12 divisors, 19 antidivisors and 1150704 totatives.
2307484 has a triangular digit sum 28 in base 10.
2307484 = 5768722 - 5768702 = 15202 - 542 is the difference of 2 nonnegative squares in 2 ways.
2307484 is the difference of 2 positive pentagonal numbers in 3 ways.
2307484 is not the sum of 3 positive squares.
23074842 = 3399842 + 22823002 is the sum of 2 positive squares in 1 way.
23074842 is the sum of 3 positive squares.
2307484 is a proper divisor of 379732 - 1.

Wednesday, June 5, 2019

Number of the day: 909307

Properties of the number 909307:

909307 is a cyclic number.
909307 = 7 × 129901 is semiprime and squarefree.
909307 has 2 distinct prime factors, 4 divisors, 19 antidivisors and 779400 totatives.
909307 has a triangular digit sum 28 in base 10.
Reversing the decimal digits of 909307 results in an emirpimes.
909307 = 193 + 533 + 913 is the sum of 3 positive cubes in 1 way.
909307 = 4546542 - 4546532 = 649542 - 649472 is the difference of 2 nonnegative squares in 2 ways.
909307 is the difference of 2 positive pentagonal numbers in 2 ways.
909307 = 1532 + 1632 + 9272 is the sum of 3 positive squares.
9093072 = 4397402 + 7959072 is the sum of 2 positive squares in 1 way.
9093072 is the sum of 3 positive squares.
909307 is a proper divisor of 113433 - 1.
909307 is an emirpimes in (at least) the following bases: 2, 10, 14, 16, 17, 21, 23, 25, 28, 30, 34, 37, 38, 40, 51, 53, 54, 56, 59, 61, 73, 78, 79, 81, 84, 85, 86, 87, 93, and 95.

Monday, June 3, 2019

Number of the day: 462130872

Properties of the number 462130872:

462130872 = 23 × 3 × 7 × 2750779 is the 437669513th composite number and is not squarefree.
462130872 has 4 distinct prime factors, 32 divisors, 69 antidivisors and 132037344 totatives.
462130872 has a semiprime digit sum 33 in base 10.
462130872 = 1155327192 - 1155327172 = 577663612 - 577663572 = 385109092 - 385109032 = 192554592 - 192554472 = 165046812 - 165046672 = 82523512 - 82523232 = 55015792 - 55015372 = 27508212 - 27507372 is the difference of 2 nonnegative squares in 8 ways.
462130872 = 2422 + 7722 + 214822 is the sum of 3 positive squares.
4621308722 is the sum of 3 positive squares.
462130872 is a proper divisor of 71305642 - 1.
462130872 = '46213087' + '2' is the concatenation of 2 prime numbers.

Sunday, June 2, 2019

Number of the day: 9331

Properties of the number 9331:

9331 = 7 × 31 × 43 is a sphenic number and squarefree.
9331 has 3 distinct prime factors, 8 divisors, 9 antidivisors and 7560 totatives.
Reversing the decimal digits of 9331 results in a semiprime.
9331 = 192 + … + 322 is the sum of at least 2 consecutive positive squares in 1 way.
9331 = 203 + 113 is the sum of 2 positive cubes in 1 way.
9331 = 46662 - 46652 = 6702 - 6632 = 1662 - 1352 = 1302 - 872 is the difference of 2 nonnegative squares in 4 ways.
9331 is the sum of 2 positive triangular numbers.
9331 is the difference of 2 positive pentagonal numbers in 4 ways.
9331 = 92 + 412 + 872 is the sum of 3 positive squares.
93312 is the sum of 3 positive squares.
9331 is a proper divisor of 376 - 1.
9331 is palindromic in (at least) the following bases: 6, 36, 53, -6, and -37.
9331 in base 6 = 111111 and consists of only the digit '1'.
9331 in base 35 = 7ll and consists of only the digits '7' and 'l'.
9331 in base 36 = 777 and consists of only the digit '7'.
9331 in base 52 = 3NN and consists of only the digits '3' and 'N'.
9331 in base 53 = 3H3 and consists of only the digits '3' and 'H'.

The number 9331 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A003464: a(n) = (6^n - 1)/5.
A005937: Pseudoprimes to base 6.
A022170: Triangle of Gaussian binomial coefficients [ n,k ] for q = 6.
A023037: a(n) = n^0+n^1+...+n^(n-1), or a(n) = (n^n-1)/(n-1) with a(0)=0; a(1)=1.
A025012: Central heptanomial coefficients: largest coefficient of (1+x+...+x^6)^n.
A053700: a(n) = 111111 in base n.
A057075: Table read by antidiagonals of T(n,k)=floor[n^n/k] with n,k >= 1.
A125118: Triangle read by rows: T(n,k) = value of the n-th repunit in base (k+1) representation, 1<=k<=n.
A201552: Square array read by diagonals: T(n,k) = number of arrays of n integers in -k..k with sum equal to 0.
A262508: Numbers that occur only once in A155043; positions of zeros in A262505, ones in A262507.

Saturday, June 1, 2019

Number of the day: 3816

Properties of the number 3816:

3816 = 23 × 32 × 53 is the 3286th composite number and is not squarefree.
3816 has 3 distinct prime factors, 24 divisors, 9 antidivisors and 1248 totatives.
3816 has a Fibonacci digit product 144 in base 10.
3816 = 73 + 93 + 143 is the sum of 3 positive cubes in 1 way.
3816 = 9552 - 9532 = 4792 - 4752 = 3212 - 3152 = 1652 - 1532 = 1152 - 972 = 712 - 352 is the difference of 2 nonnegative squares in 6 ways.
3816 is the difference of 2 positive pentagonal numbers in 1 way.
3816 = 302 + 542 is the sum of 2 positive squares in 1 way.
3816 = 142 + 162 + 582 is the sum of 3 positive squares.
38162 = 20162 + 32402 is the sum of 2 positive squares in 1 way.
38162 is the sum of 3 positive squares.
3816 is a proper divisor of 1072 - 1.
3816 = '381' + '6' is the concatenation of 2 semiprime numbers.
3816 is palindromic in (at least) the following bases: 31, 71, and -41.
3816 in base 16 = ee8 and consists of only the digits '8' and 'e'.
3816 in base 19 = aag and consists of only the digits 'a' and 'g'.
3816 in base 31 = 3u3 and consists of only the digits '3' and 'u'.
3816 in base 43 = 22W and consists of only the digits '2' and 'W'.
3816 in base 61 = 11Y and consists of only the digits '1' and 'Y'.

The number 3816 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A000567: Octagonal numbers: n*(3*n-2). Also called star numbers.
A014642: Even octagonal numbers: 4*n*(3*n-1).
A118807: Number of partitions of n having no parts with multiplicity 3.
A135190: Numbers n that raised to the powers from 1 to k (with k>=1) are multiple of the sum of their digits (n raised to k+1 must not be a multiple). Case k=5.
A138990: a(n) = Frobenius number for 4 successive primes = F[p(n),p(n+1),p(n+2),p(n+3)].
A139229: First differences of perfect numbers A000396, divided by 2.
A173682: Number of ways of writing n as a sum of 9 nonnegative cubes.
A219047: Numbers n such that 3^n - 28 is prime.
A257211: Numbers n such that the decimal expansions of both n and n^2 have 1 as smallest digit and 8 as largest digit.
A269656: T(n,k)=Number of length-n 0..k arrays with no adjacent pair x,x+1 repeated.

Friday, May 31, 2019

Number of the day: 950

Properties of the number 950:

950 = 2 × 52 × 19 is the 788th composite number and is not squarefree.
950 has 3 distinct prime factors, 12 divisors, 9 antidivisors and 360 totatives.
950 has a semiprime digit sum 14 in base 10.
950 is the difference of 2 positive pentagonal numbers in 2 ways.
950 = 32 + 102 + 292 is the sum of 3 positive squares.
9502 = 5702 + 7602 = 2662 + 9122 is the sum of 2 positive squares in 2 ways.
9502 is the sum of 3 positive squares.
950 is a proper divisor of 1512 - 1.
950 is palindromic in (at least) the following bases: 37, 49, 94, -15, and -73.
950 in base 6 = 4222 and consists of only the digits '2' and '4'.
950 in base 7 = 2525 and consists of only the digits '2' and '5'.
950 in base 8 = 1666 and consists of only the digits '1' and '6'.
950 in base 30 = 11k and consists of only the digits '1' and 'k'.

The number 950 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A000601: Expansion of 1/((1-x)^2*(1-x^2)*(1-x^3)).
A001318: Generalized pentagonal numbers: m*(3*m - 1)/2, m = 0, +-1, +-2, +-3, ....
A005449: Second pentagonal numbers: a(n) = n*(3*n + 1)/2.
A023894: Number of partitions of n into prime power parts (1 excluded).
A024702: a(n) = (prime(n)^2 - 1)/24.
A028338: Triangle of coefficients in expansion of (x+1)*(x+3)*...*(x + 2n - 1) in rising powers of x.
A028895: 5 times triangular numbers: a(n) = 5*n*(n+1)/2.
A035959: Number of partitions of n in which no parts are multiples of 5.
A084646: Hypotenuses for which there exist exactly 2 distinct integer triangles.
A304714: Number of connected strict integer partitions of n.

Thursday, May 30, 2019

Number of the day: 586134

Properties of the number 586134:

586134 = 2 × 32 × 32563 is the 538078th composite number and is not squarefree.
586134 has 3 distinct prime factors, 12 divisors, 13 antidivisors and 195372 totatives.
586134 is the sum of 2 positive triangular numbers.
586134 = 172 + 822 + 7612 is the sum of 3 positive squares.
5861342 is the sum of 3 positive squares.
586134 is a proper divisor of 541201 - 1.
586134 = '58' + '6134' is the concatenation of 2 semiprime numbers.

Tuesday, May 28, 2019

Number of the day: 71311

Properties of the number 71311:

71311 is a cyclic number.
71311 = 29 × 2459 is semiprime and squarefree.
71311 has 2 distinct prime factors, 4 divisors, 27 antidivisors and 68824 totatives.
71311 has an emirp digit sum 13 in base 10.
71311 has a Fibonacci digit sum 13 in base 10.
71311 has a semiprime digit product 21 in base 10.
71311 has a Fibonacci digit product 21 in base 10.
71311 has a triangular digit product 21 in base 10.
Reversing the decimal digits of 71311 results in a prime.
71311 = 356562 - 356552 = 12442 - 12152 is the difference of 2 nonnegative squares in 2 ways.
71311 is the sum of 2 positive triangular numbers.
71311 is the difference of 2 positive pentagonal numbers in 2 ways.
71311 is not the sum of 3 positive squares.
713112 = 491802 + 516392 is the sum of 2 positive squares in 1 way.
713112 is the sum of 3 positive squares.
71311 is a proper divisor of 591229 - 1.
71311 = '71' + '311' is the concatenation of 2 emirps.
71311 is an emirpimes in (at least) the following bases: 5, 7, 9, 14, 15, 21, 23, 25, 26, 28, 29, 31, 33, 34, 35, 36, 37, 38, 39, 47, 55, 56, 61, 63, 65, 68, 69, 71, 79, 83, 85, 89, 93, 95, 96, 97, and 100.
71311 is palindromic in (at least) the following bases: -48, -53, and -56.
71311 in base 44 = aaV and consists of only the digits 'V' and 'a'.
71311 in base 52 = QJJ and consists of only the digits 'J' and 'Q'.
71311 in base 54 = OOV and consists of only the digits 'O' and 'V'.
71311 in base 55 = NVV and consists of only the digits 'N' and 'V'.

Monday, May 27, 2019

Number of the day: 65919

Properties of the number 65919:

65919 = 3 × 7 × 43 × 73 is the 59336th composite number and is squarefree.
65919 has 4 distinct prime factors, 16 divisors, 15 antidivisors and 36288 totatives.
65919 has a sphenic digit sum 30 in base 10.
65919 has an oblong digit sum 30 in base 10.
65919 = 622 + … + 752 is the sum of at least 2 consecutive positive squares in 1 way.
65919 = 329602 - 329592 = 109882 - 109852 = 47122 - 47052 = 15802 - 15592 = 7882 - 7452 = 4882 - 4152 = 3202 - 1912 = 2602 - 412 is the difference of 2 nonnegative squares in 8 ways.
65919 is the sum of 2 positive triangular numbers.
65919 is the difference of 2 positive pentagonal numbers in 3 ways.
65919 is not the sum of 3 positive squares.
659192 = 433442 + 496652 is the sum of 2 positive squares in 1 way.
659192 is the sum of 3 positive squares.
65919 is a proper divisor of 15973 - 1.
65919 = '659' + '19' is the concatenation of 2 prime numbers.
65919 = '6' + '5919' is the concatenation of 2 semiprime numbers.
65919 in base 60 = IId and consists of only the digits 'I' and 'd'.

The number 65919 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A129212: Numbers n such that n^3 divides 4^(n^2)-1.
A186570: T(n,k)=Number of (n+2)X(k+2) 0..5 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock
A249614: Integers that reach the (47360, 29127) cycle described in A234534, after iterations of numerator(sigma(n)/n) = A017665(n).

Sunday, May 26, 2019

Number of the day: 829600

Properties of the number 829600:

829600 = 25 × 52 × 17 × 61 is the 763470th composite number and is not squarefree.
829600 has 4 distinct prime factors, 72 divisors, 15 antidivisors and 307200 totatives.
829600 has a semiprime digit sum 25 in base 10.
829600 is the difference of 2 nonnegative squares in 24 ways.
829600 is the difference of 2 positive pentagonal numbers in 5 ways.
829600 = 3002 + 8602 = 1402 + 9002 = 6362 + 6522 = 5082 + 7562 = 4282 + 8042 = 2762 + 8682 is the sum of 2 positive squares in 6 ways.
829600 = 682 + 2402 + 8762 is the sum of 3 positive squares.
8296002 = 3904002 + 7320002 = 2520002 + 7904002 = 5160002 + 6496002 = 1268802 + 8198402 = 230402 + 8292802 = 2726402 + 7835202 = 3513602 + 7515202 = 2100802 + 8025602 = 4811202 + 6758402 = 5797442 + 5934082 = 4632322 + 6882242 = 4791362 + 6772482 = 1698242 + 8120322 = 206082 + 8293442 = 3134722 + 7680962 = 4977602 + 6636802 = 3699202 + 7425602 = 5630402 + 6092802 = 1496002 + 8160002 = 2322882 + 7964162 = 848642 + 8252482 = 3720962 + 7414722 is the sum of 2 positive squares in 22 ways.
8296002 is the sum of 3 positive squares.
829600 is a proper divisor of 5994 - 1.

The number 829600 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A209346: Number of 5-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero with no three beads in a row equal.

Saturday, May 25, 2019

Number of the day: 24682

Properties of the number 24682:

24682 = 2 × 7 × 41 × 43 is the 21949th composite number and is squarefree.
24682 has 4 distinct prime factors, 16 divisors, 17 antidivisors and 10080 totatives.
24682 has a semiprime digit sum 22 in base 10.
Reversing the decimal digits of 24682 results in a semiprime.
24682 is the sum of 2 positive triangular numbers.
24682 is the difference of 2 positive pentagonal numbers in 5 ways.
24682 = 242 + 652 + 1412 is the sum of 3 positive squares.
246822 = 54182 + 240802 is the sum of 2 positive squares in 1 way.
246822 is the sum of 3 positive squares.
24682 is a proper divisor of 17212 - 1.
24682 is palindromic in (at least) the following bases: 48, 62, and -9.
24682 in base 18 = 4434 and consists of only the digits '3' and '4'.
24682 in base 48 = AYA and consists of only the digits 'A' and 'Y'.
24682 in base 55 = 88g and consists of only the digits '8' and 'g'.
24682 in base 61 = 6cc and consists of only the digits '6' and 'c'.
24682 in base 62 = 6Q6 and consists of only the digits '6' and 'Q'.

The number 24682 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A000970: Fermat coefficients.
A008646: Molien series for cyclic group of order 5.
A051170: T(n,5), array T as in A051168; a count of Lyndon words; aperiodic necklaces with 5 black beads and n-5 white beads.
A065345: a(n) = Mod( binomial(2*n,n), (n+1)*(n+2)*(n+3) ).
A157363: 686n - 14.
A234042: a(n) = C(n+4,4)*gcd(n,5)/5.
A234513: 8*binomial(9*n+8,n)/(9*n+8).
A241546: Number of partitions p of n such that (number of numbers of the form 3k in p) is a part of p.
A259110: 2*A000447(n).
A263226: a(n) = 15*n^2 - 13*n.

Friday, May 24, 2019

Number of the day: 28338496

Properties of the number 28338496:

28338496 = 26 × 442789 is the 26577260th composite number and is not squarefree.
28338496 has 2 distinct prime factors, 14 divisors, 37 antidivisors and 14169216 totatives.
28338496 has a prime digit sum 43 in base 10.
Reversing the decimal digits of 28338496 results in a semiprime.
28338496 = 70846252 - 70846232 = 35423142 - 35423102 = 17711602 - 17711522 = 8855862 - 8855702 = 4428052 - 4427732 is the difference of 2 nonnegative squares in 5 ways.
28338496 is the difference of 2 positive pentagonal numbers in 1 way.
28338496 = 14002 + 51362 is the sum of 2 positive squares in 1 way.
28338496 = 3842 + 9042 + 52322 is the sum of 3 positive squares.
283384962 = 143808002 + 244184962 is the sum of 2 positive squares in 1 way.
283384962 is the sum of 3 positive squares.
28338496 is a proper divisor of 64136899 - 1.

Thursday, May 23, 2019

Number of the day: 583006392

Edward Norton Lorenz was born on this day 102 years ago.

Properties of the number 583006392:

583006392 = 23 × 32 × 23 × 352057 is the 552523140th composite number and is not squarefree.
583006392 has 4 distinct prime factors, 48 divisors, 39 antidivisors and 185885568 totatives.
583006392 has a triangular digit sum 36 in base 10.
583006392 is the difference of 2 nonnegative squares in 12 ways.
583006392 is the difference of 2 positive pentagonal numbers in 2 ways.
583006392 = 222 + 4122 + 241422 is the sum of 3 positive squares.
5830063922 = 1147690802 + 5715982082 is the sum of 2 positive squares in 1 way.
5830063922 is the sum of 3 positive squares.
583006392 is a proper divisor of 82958676 - 1.

Wednesday, May 22, 2019

Number of the day: 43812311292

Properties of the number 43812311292:

43812311292 = 22 × 34 × 47 × 1229 × 2341 is composite and not squarefree.
43812311292 has 5 distinct prime factors, 120 divisors, 47 antidivisors and 14275647360 totatives.
43812311292 has a triangular digit sum 36 in base 10.
43812311292 is the difference of 2 nonnegative squares in 20 ways.
43812311292 is the sum of 2 positive triangular numbers.
43812311292 is the difference of 2 positive pentagonal numbers in 2 ways.
43812311292 is not the sum of 3 positive squares.
438123112922 = 296903361602 + 322180471082 = 258269925602 + 353904658922 = 216274147202 + 381021463082 = 49908247202 + 435271213082 is the sum of 2 positive squares in 4 ways.
438123112922 is the sum of 3 positive squares.
43812311292 is a proper divisor of 18612484 - 1.

Tuesday, May 21, 2019

Number of the day: 250514

Properties of the number 250514:

250514 = 2 × 11 × 59 × 193 is the 228435th composite number and is squarefree.
250514 has 4 distinct prime factors, 16 divisors, 9 antidivisors and 111360 totatives.
250514 has an emirp digit sum 17 in base 10.
250514 is the difference of 2 positive pentagonal numbers in 4 ways.
250514 = 282 + 932 + 4912 is the sum of 3 positive squares.
2505142 = 1233102 + 2180642 is the sum of 2 positive squares in 1 way.
2505142 is the sum of 3 positive squares.
250514 is a proper divisor of 70960 - 1.
250514 is palindromic in (at least) base 98.

Monday, May 20, 2019

Number of the day: 995262831

Properties of the number 995262831:

995262831 = 32 × 23 × 4808033 is the 944643956th composite number and is not squarefree.
995262831 has 3 distinct prime factors, 12 divisors, 17 antidivisors and 634660224 totatives.
995262831 has a triangular digit sum 45 in base 10.
995262831 = 4976314162 - 4976314152 = 1658771402 - 1658771372 = 552923842 - 552923752 = 216361602 - 216361372 = 72120842 - 72120152 = 24041202 - 24039132 is the difference of 2 nonnegative squares in 6 ways.
995262831 is the sum of 2 positive triangular numbers.
995262831 is the difference of 2 positive pentagonal numbers in 2 ways.
995262831 is not the sum of 3 positive squares.
9952628312 = 2988283052 + 9493417442 is the sum of 2 positive squares in 1 way.
9952628312 is the sum of 3 positive squares.
995262831 is a proper divisor of 47901506 - 1.
995262831 = '995' + '262831' is the concatenation of 2 semiprime numbers.

Sunday, May 19, 2019

Number of the day: 44681

Properties of the number 44681:

44681 = 7 × 13 × 491 is a sphenic number and squarefree.
44681 has 3 distinct prime factors, 8 divisors, 11 antidivisors and 35280 totatives.
44681 has a prime digit sum 23 in base 10.
44681 = 223412 - 223402 = 31952 - 31882 = 17252 - 17122 = 2912 - 2002 is the difference of 2 nonnegative squares in 4 ways.
44681 is the difference of 2 positive pentagonal numbers in 3 ways.
44681 = 312 + 542 + 2022 is the sum of 3 positive squares.
446812 = 171852 + 412442 is the sum of 2 positive squares in 1 way.
446812 is the sum of 3 positive squares.
44681 is a proper divisor of 98312 - 1.
44681 = '4' + '4681' is the concatenation of 2 semiprime numbers.
44681 is palindromic in (at least) the following bases: -8, and -38.

The number 44681 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A016261: Expansion of 1/((1-x)*(1-9*x)*(1-10*x)).
A021404: Expansion of 1/((1-x)(1-3x)(1-4x)(1-12x)).
A156754: Numerator of Euler(n, 7/20).
A184322: Number of strings of numbers x(i=1..7) in 0..n with sum i^2*x(i)^3 equal to 49*n^3
A274037: Numbers k such that 3*10^k - 49 is prime.

Saturday, May 18, 2019

Number of the day: 4842497080

Bertrand Russell was born on this day 147 years ago.

Properties of the number 4842497080:

4842497080 = 23 × 5 × 121062427 is the 4614599637th composite number and is not squarefree.
4842497080 has 3 distinct prime factors, 16 divisors, 15 antidivisors and 1936998816 totatives.
4842497080 has a semiprime digit sum 46 in base 10.
4842497080 = 12106242712 - 12106242692 = 6053121372 - 6053121332 = 2421248592 - 2421248492 = 1210624372 - 1210624172 is the difference of 2 nonnegative squares in 4 ways.
4842497080 is the sum of 2 positive triangular numbers.
4842497080 is the difference of 2 positive pentagonal numbers in 2 ways.
4842497080 = 21002 + 21862 + 695222 is the sum of 3 positive squares.
48424970802 = 29054982482 + 38739976642 is the sum of 2 positive squares in 1 way.
48424970802 is the sum of 3 positive squares.
4842497080 is a proper divisor of 4120177071 - 1.

Friday, May 17, 2019

Number of the day: 579716

Properties of the number 579716:

579716 = 22 × 37 × 3917 is the 532148th composite number and is not squarefree.
579716 has 3 distinct prime factors, 12 divisors, 39 antidivisors and 281952 totatives.
579716 has a semiprime digit sum 35 in base 10.
579716 = 1449302 - 1449282 = 39542 - 38802 is the difference of 2 nonnegative squares in 2 ways.
579716 is the difference of 2 positive pentagonal numbers in 2 ways.
579716 = 2902 + 7042 = 462 + 7602 is the sum of 2 positive squares in 2 ways.
579716 = 742 + 1962 + 7322 is the sum of 3 positive squares.
5797162 = 4083202 + 4115162 = 1880162 + 5483802 = 699202 + 5754842 = 2527842 + 5217002 is the sum of 2 positive squares in 4 ways.
5797162 is the sum of 3 positive squares.
579716 is a proper divisor of 1087132 - 1.
579716 = '57971' + '6' is the concatenation of 2 semiprime numbers.

Thursday, May 16, 2019

Number of the day: 869452037868

Pafnuty Lvovich Chebyshev was born on this day 198 years ago.

Properties of the number 869452037868:

869452037868 = 22 × 3 × 19 × 23 × 7523 × 22039 is composite and not squarefree.
869452037868 has 6 distinct prime factors, 96 divisors, 43 antidivisors and 262579420224 totatives.
869452037868 has a sphenic digit sum 66 in base 10.
869452037868 has a triangular digit sum 66 in base 10.
869452037868 is the difference of 2 nonnegative squares in 16 ways.
869452037868 is the sum of 2 positive triangular numbers.
869452037868 is the difference of 2 positive pentagonal numbers in 7 ways.
869452037868 = 16822 + 29302 + 9324382 is the sum of 3 positive squares.
8694520378682 is the sum of 3 positive squares.
869452037868 is a proper divisor of 1319248226 - 1.

Wednesday, May 15, 2019

Number of the day: 4488072

Properties of the number 4488072:

4488072 = 23 × 3 × 187003 is the 4172892th composite number and is not squarefree.
4488072 has 3 distinct prime factors, 16 divisors, 15 antidivisors and 1496016 totatives.
4488072 has a semiprime digit sum 33 in base 10.
4488072 = 11220192 - 11220172 = 5610112 - 5610072 = 3740092 - 3740032 = 1870092 - 1869972 is the difference of 2 nonnegative squares in 4 ways.
4488072 is the sum of 2 positive triangular numbers.
4488072 = 322 + 2622 + 21022 is the sum of 3 positive squares.
44880722 is the sum of 3 positive squares.
4488072 is a proper divisor of 2416926 - 1.
4488072 = '448807' + '2' is the concatenation of 2 prime numbers.

Tuesday, May 14, 2019

Number of the day: 3102432396

Properties of the number 3102432396:

3102432396 = 22 × 3 × 7 × 2069 × 17851 is the 2953292890th composite number and is not squarefree.
3102432396 has 5 distinct prime factors, 48 divisors, 27 antidivisors and 885931200 totatives.
3102432396 has a semiprime digit sum 33 in base 10.
Reversing the decimal digits of 3102432396 results in a sphenic number.
3102432396 = 7756081002 - 7756080982 = 2585360362 - 2585360302 = 1108011642 - 1108011502 = 369337402 - 369336982 = 3769402 - 3728022 = 1311642 - 1187502 = 680362 - 390702 = 613002 - 255982 is the difference of 2 nonnegative squares in 8 ways.
3102432396 is the difference of 2 positive pentagonal numbers in 4 ways.
3102432396 = 6462 + 24462 + 556422 is the sum of 3 positive squares.
31024323962 = 12280773962 + 28490196002 is the sum of 2 positive squares in 1 way.
31024323962 is the sum of 3 positive squares.
3102432396 is a proper divisor of 64728050 - 1.

Monday, May 13, 2019

Number of the day: 8794

Properties of the number 8794:

8794 = 2 × 4397 is semiprime and squarefree.
8794 has 2 distinct prime factors, 4 divisors, 17 antidivisors and 4396 totatives.
8794 has a triangular digit sum 28 in base 10.
8794 has a triangular digit product 2016 in base 10.
Reversing the decimal digits of 8794 results in a sphenic number.
8794 is the sum of 2 positive triangular numbers.
8794 is the difference of 2 positive pentagonal numbers in 2 ways.
8794 = 352 + 872 is the sum of 2 positive squares in 1 way.
8794 = 122 + 552 + 752 is the sum of 3 positive squares.
87942 = 60902 + 63442 is the sum of 2 positive squares in 1 way.
87942 is the sum of 3 positive squares.
8794 is a proper divisor of 7157 - 1.
8794 = '87' + '94' is the concatenation of 2 semiprime numbers.
8794 is an emirpimes in (at least) the following bases: 2, 3, 4, 14, 18, 19, 24, 26, 29, 30, 37, 45, 46, 60, 68, 69, 76, 77, 83, 85, 89, 93, 94, 98, and 100.
8794 is palindromic in (at least) the following bases: 56, and -59.
8794 in base 21 = jjg and consists of only the digits 'g' and 'j'.
8794 in base 55 = 2nn and consists of only the digits '2' and 'n'.
8794 in base 56 = 2j2 and consists of only the digits '2' and 'j'.

The number 8794 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A096403: Number of partitions of n in which number of least parts is equal to least part.
A126283: Largest number k for which the n-th prime is the median of the largest prime dividing the first k integers.
A129311: Numbers n such that 6*p(n)*p(n+1)*p(n+2)*p(n+3)*p(n+4)*p(n+5)-1 and 6*p(n)*p(n+1)*p(n+2)*p(n+3)*p(n+4)*p(n+5)+1 are twin primes with p(n)=n-th prime.
A206423: Fibonacci sequence beginning 12, 7.
A237871: Number of partitions of n such that (greatest part) + (least part) > number of parts.
A243718: Number of inequivalent (mod D_8) ways to place 3 nonattacking knights on an n X n board.
A270683: Partial sums of the number of active (ON,black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 190", based on the 5-celled von Neumann neighborhood.
A301381: Number of tied close American football games: number of ways for the game to end at the score of n to n and never be separated by more than one score after each play.
A301604: Number of nX4 0..1 arrays with every element equal to 0, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.
A301608: T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.

Sunday, May 12, 2019

Number of the day: 54199161

Properties of the number 54199161:

54199161 = 32 × 6022129 is the 50961795th composite number and is not squarefree.
54199161 has 2 distinct prime factors, 6 divisors, 13 antidivisors and 36132768 totatives.
54199161 has a triangular digit sum 36 in base 10.
54199161 = 270995812 - 270995802 = 90331952 - 90331922 = 30110692 - 30110602 is the difference of 2 nonnegative squares in 3 ways.
54199161 is the sum of 2 positive triangular numbers.
54199161 is the difference of 2 positive pentagonal numbers in 1 way.
54199161 = 29252 + 67562 is the sum of 2 positive squares in 1 way.
54199161 = 892 + 2262 + 73582 is the sum of 3 positive squares.
541991612 = 370879112 + 395226002 is the sum of 2 positive squares in 1 way.
541991612 is the sum of 3 positive squares.
54199161 is a proper divisor of 52171692 - 1.
54199161 = '5419' + '9161' is the concatenation of 2 prime numbers.
54199161 = '54199' + '161' is the concatenation of 2 semiprime numbers.

Saturday, May 11, 2019

Number of the day: 2553

Properties of the number 2553:

2553 = 3 × 23 × 37 is a sphenic number and squarefree.
2553 has 3 distinct prime factors, 8 divisors, 9 antidivisors and 1584 totatives.
2553 has an emirpimes digit sum 15 in base 10.
2553 has a triangular digit sum 15 in base 10.
2553 = 12772 - 12762 = 4272 - 4242 = 672 - 442 = 532 - 162 is the difference of 2 nonnegative squares in 4 ways.
2553 is the difference of 2 positive pentagonal numbers in 1 way.
2553 = 22 + 72 + 502 is the sum of 3 positive squares.
25532 = 8282 + 24152 is the sum of 2 positive squares in 1 way.
25532 is the sum of 3 positive squares.
2553 is a proper divisor of 9194 - 1.
2553 is palindromic in (at least) the following bases: 2, 16, 19, 44, 68, -30, -34, -58, and -88.
2553 in base 11 = 1a11 and consists of only the digits '1' and 'a'.
2553 in base 16 = 9f9 and consists of only the digits '9' and 'f'.
2553 in base 18 = 7ff and consists of only the digits '7' and 'f'.
2553 in base 19 = 717 and consists of only the digits '1' and '7'.
2553 in base 29 = 311 and consists of only the digits '1' and '3'.
2553 in base 35 = 22x and consists of only the digits '2' and 'x'.
2553 in base 43 = 1GG and consists of only the digits '1' and 'G'.
2553 in base 44 = 1E1 and consists of only the digits '1' and 'E'.
2553 in base 50 = 113 and consists of only the digits '1' and '3'.

The number 2553 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A001891: Hit polynomials; convolution of natural numbers with Fibonacci numbers F(2), F(3), F(4),....
A007853: Number of maximal antichains in rooted plane trees on n nodes.
A008778: a(n) = (n+1)*(n^2+8n+6)/6. Number of n-dimensional partitions of 4. Number of terms in 4th derivative of a function composed with itself n times.
A048701: List of binary palindromes of even length (written in base 10).
A051624: 12-gonal (or dodecagonal) numbers: a(n) = n*(5*n-4).
A056108: Fourth spoke of a hexagonal spiral.
A063489: a(n) = (2*n-1)*(5*n^2-5*n+6)/6.
A071355: a(n) = 2*n^2 + 11*n + 12.
A195162: Generalized 12-gonal numbers: k*(5*k-4) for k = 0, +-1, +-2, ...
A299285: Coordination sequence for "tea" 3D uniform tiling.

Friday, May 10, 2019

Number of the day: 823935734231

Properties of the number 823935734231:

823935734231 is a cyclic number.
823935734231 = 83 × 89 × 6553 × 17021 is composite and squarefree.
823935734231 has 4 distinct prime factors, 16 divisors, 39 antidivisors and 804692528640 totatives.
823935734231 = 4119678671162 - 4119678671152 = 49634683202 - 49634682372 = 46288524842 - 46288523952 = 628703402 - 628637872 = 557730002 - 557656132 = 242120162 - 241949952 = 10293842 - 4854852 = 9979802 - 4147632 is the difference of 2 nonnegative squares in 8 ways.
823935734231 is the difference of 2 positive pentagonal numbers in 8 ways.
823935734231 is not the sum of 3 positive squares.
8239357342312 = 4803612627192 + 6694200112202 = 8435014442 + 8239353024652 = 2646256069752 + 7802841676442 = 3610504902812 + 7406163903202 = 1376124701442 + 8123625435752 = 3919726090652 + 7247258570562 = 2721553675562 + 7776898803852 = 2314730803192 + 7907530001402 = 5081736888952 + 6485596318442 = 3602920975352 + 7409856264442 = 1384440514602 + 8122212375692 = 5797879898442 + 5854194914552 = 4796756945052 + 6699114286562 is the sum of 2 positive squares in 13 ways.
8239357342312 is the sum of 3 positive squares.
823935734231 is a proper divisor of 997296296 - 1.
823935734231 = '82393' + '5734231' is the concatenation of 2 prime numbers.

Thursday, May 9, 2019

Number of the day: 4719335

Gaspard Monge was born on this day 273 years ago.

Properties of the number 4719335:

4719335 is a cyclic number.
4719335 = 5 × 179 × 5273 is a sphenic number and squarefree.
4719335 has 3 distinct prime factors, 8 divisors, 23 antidivisors and 3753664 totatives.
4719335 = 23596682 - 23596672 = 4719362 - 4719312 = 132722 - 130932 = 30842 - 21892 is the difference of 2 nonnegative squares in 4 ways.
4719335 is the difference of 2 positive pentagonal numbers in 3 ways.
4719335 is not the sum of 3 positive squares.
47193352 = 33159752 + 33580402 = 6379562 + 46760172 = 6968472 + 46676042 = 28316012 + 37754682 is the sum of 2 positive squares in 4 ways.
47193352 is the sum of 3 positive squares.
4719335 is a proper divisor of 3592636 - 1.
4719335 = '471' + '9335' is the concatenation of 2 semiprime numbers.

Wednesday, May 8, 2019

Number of the day: 6440

Properties of the number 6440:

6440 = 23 × 5 × 7 × 23 is the 5603th composite number and is not squarefree.
6440 has 4 distinct prime factors, 32 divisors, 19 antidivisors and 2112 totatives.
6440 has a semiprime digit sum 14 in base 10.
6440 = (20 × 21)/2 + … + (35 × 36)/2 is the sum of at least 2 consecutive triangular numbers in 1 way.
6440 = 16112 - 16092 = 8072 - 8032 = 3272 - 3172 = 2372 - 2232 = 1712 - 1512 = 1292 - 1012 = 932 - 472 = 812 - 112 is the difference of 2 nonnegative squares in 8 ways.
6440 is the difference of 2 positive pentagonal numbers in 3 ways.
6440 = 102 + 162 + 782 is the sum of 3 positive squares.
64402 = 38642 + 51522 is the sum of 2 positive squares in 1 way.
64402 is the sum of 3 positive squares.
6440 is a proper divisor of 1392 - 1.
6440 is palindromic in (at least) the following bases: 21, 33, 41, 91, -19, -39, -58, and -74.
6440 in base 3 = 22211112 and consists of only the digits '1' and '2'.
6440 in base 12 = 3888 and consists of only the digits '3' and '8'.
6440 in base 21 = ece and consists of only the digits 'c' and 'e'.
6440 in base 33 = 5u5 and consists of only the digits '5' and 'u'.
6440 in base 41 = 3Y3 and consists of only the digits '3' and 'Y'.

The number 6440 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A007742: a(n) = n*(4*n+1).
A033587: a(n) = 2*n*(4*n + 3).
A045944: Rhombic matchstick numbers: a(n) = n*(3*n+2).
A078355: Minimal (positive) solution a(n) of Pell equation b(n)^2 - D(n)*a(n)^2 = +4 with D(n)= A077425(n). The companion sequence is a(n)=A077428(n).
A085146: Numbers n such that n!!!!+1 is prime.
A163934: Triangle related to the asymptotic expansion of E(x,m=4,n).
A175525: Numbers n such that n divides the sum of digits of 13^n.
A196856: T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,1,0,2,4 for x=0,1,2,3,4
A234140: T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 9
A304638: a(n) equals the coefficient of x^n in Sum_{m>=0} (x^m + 1/x^m)^m for n > 0.

Tuesday, May 7, 2019

Number of the day: 120544

Properties of the number 120544:

120544 = 25 × 3767 is the 109201th composite number and is not squarefree.
120544 has 2 distinct prime factors, 12 divisors, 17 antidivisors and 60256 totatives.
Reversing the decimal digits of 120544 results in a prime.
120544 = 301372 - 301352 = 150702 - 150662 = 75382 - 75302 = 37752 - 37592 is the difference of 2 nonnegative squares in 4 ways.
120544 is the difference of 2 positive pentagonal numbers in 2 ways.
120544 = 1322 + 2042 + 2482 is the sum of 3 positive squares.
1205442 is the sum of 3 positive squares.
120544 is a proper divisor of 74328 - 1.
120544 is palindromic in (at least) the following bases: 55, and -66.
120544 in base 55 = dkd and consists of only the digits 'd' and 'k'.

The number 120544 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A213586: Antidiagonal sums of the convolution array A213584.

Monday, May 6, 2019

Number of the day: 7735

André Weil was born on this day 113 years ago.

Properties of the number 7735:

7735 is a cyclic number.
7735 = 5 × 7 × 13 × 17 is the 6753th composite number and is squarefree.
7735 has 4 distinct prime factors, 16 divisors, 25 antidivisors and 4608 totatives.
7735 has a semiprime digit sum 22 in base 10.
Reversing the decimal digits of 7735 results in a semiprime.
7735 = (26 × 27)/2 + … + (39 × 40)/2 = (6 × 7)/2 + … + (35 × 36)/2 is the sum of at least 2 consecutive triangular numbers in 2 ways.
7735 = 38682 - 38672 = 7762 - 7712 = 5562 - 5492 = 3042 - 2912 = 2362 - 2192 = 1282 - 932 = 922 - 272 = 882 - 32 is the difference of 2 nonnegative squares in 8 ways.
7735 is the sum of 2 positive triangular numbers.
7735 is the difference of 2 positive pentagonal numbers in 6 ways.
7735 is not the sum of 3 positive squares.
77352 = 36402 + 68252 = 11832 + 76442 = 32762 + 70072 = 40322 + 66012 = 7352 + 77002 = 52082 + 57192 = 49002 + 59852 = 3292 + 77282 = 18482 + 75112 = 29752 + 71402 = 19042 + 74972 = 39272 + 66642 = 46412 + 61882 is the sum of 2 positive squares in 13 ways.
77352 is the sum of 3 positive squares.
7735 is a proper divisor of 14292 - 1.
7735 = '773' + '5' is the concatenation of 2 prime numbers.
7735 = '77' + '35' is the concatenation of 2 semiprime numbers.
7735 is palindromic in (at least) base 90.
7735 in base 23 = ee7 and consists of only the digits '7' and 'e'.
7735 in base 26 = bbd and consists of only the digits 'b' and 'd'.

The number 7735 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A005581: a(n) = (n-1)*n*(n+4)/6.
A032164: Number of aperiodic necklaces of n beads of 6 colors; dimensions of free Lie algebras.
A074650: Table T(n,k) read by downward antidiagonals: number of Lyndon words (aperiodic necklaces) with n beads of k colors, n >= 1, k >= 1.
A075147: Number of Lyndon words (aperiodic necklaces) with n beads of n colors.
A097102: Numbers n that are the hypotenuse of exactly 13 distinct integer-sided right triangles, i.e., n^2 can be written as a sum of two squares in 13 ways.
A116522: a(0)=1, a(1)=1, a(n)=7a(n/2) for n=2,4,6,..., a(n)=6a((n-1)/2)+a((n+1)/2) for n=3,5,7,....
A143325: Table T(n,k) by antidiagonals. T(n,k) is the number of length n primitive (=aperiodic or period n) k-ary words (n,k >= 1) which are earlier in lexicographic order than any other word derived by cyclic shifts of the alphabet.
A221578: A sum over partitions (q=6), see first comment.
A271580: Magic sums of 4 X 4 magic squares composed of squares.
A324315: Squarefree integers m > 1 such that if prime p divides m, then the sum of the base p digits of m is at least p.

Sunday, May 5, 2019

Number of the day: 931330

Properties of the number 931330:

931330 = 2 × 5 × 93133 is a sphenic number and squarefree.
931330 has 3 distinct prime factors, 8 divisors, 5 antidivisors and 372528 totatives.
931330 has a prime digit sum 19 in base 10.
931330 is the difference of 2 positive pentagonal numbers in 2 ways.
931330 = 6112 + 7472 = 2312 + 9372 is the sum of 2 positive squares in 2 ways.
931330 = 1922 + 2152 + 9212 is the sum of 3 positive squares.
9313302 = 5587982 + 7450642 = 1846882 + 9128342 = 4328942 + 8246082 = 3999502 + 8410802 is the sum of 2 positive squares in 4 ways.
9313302 is the sum of 3 positive squares.
931330 is a proper divisor of 1361117 - 1.

Saturday, May 4, 2019

Number of the day: 7909655

Properties of the number 7909655:

7909655 is a cyclic number.
7909655 = 5 × 13 × 121687 is a sphenic number and squarefree.
7909655 has 3 distinct prime factors, 8 divisors, 17 antidivisors and 5840928 totatives.
7909655 has a prime digit sum 41 in base 10.
Reversing the decimal digits of 7909655 results in a semiprime.
7909655 = 39548282 - 39548272 = 7909682 - 7909632 = 3042242 - 3042112 = 608762 - 608112 is the difference of 2 nonnegative squares in 4 ways.
7909655 is the difference of 2 positive pentagonal numbers in 4 ways.
7909655 is not the sum of 3 positive squares.
79096552 = 47457932 + 63277242 = 19469922 + 76662812 = 40156712 + 68144722 = 30421752 + 73012202 is the sum of 2 positive squares in 4 ways.
79096552 is the sum of 3 positive squares.
7909655 is a proper divisor of 19511193 - 1.
7909655 = '7909' + '655' is the concatenation of 2 semiprime numbers.

Friday, May 3, 2019

Number of the day: 30930

Properties of the number 30930:

30930 = 2 × 3 × 5 × 1031 is the 27596th composite number and is squarefree.
30930 has 4 distinct prime factors, 16 divisors, 9 antidivisors and 8240 totatives.
30930 has an emirpimes digit sum 15 in base 10.
30930 has a triangular digit sum 15 in base 10.
30930 is the difference of 2 positive pentagonal numbers in 2 ways.
30930 = 42 + 552 + 1672 is the sum of 3 positive squares.
309302 = 185582 + 247442 is the sum of 2 positive squares in 1 way.
309302 is the sum of 3 positive squares.
30930 is a proper divisor of 61910 - 1.
30930 = '30' + '930' is the concatenation of 2 oblong numbers.
30930 is palindromic in (at least) the following bases: 35, 45, -42, and -94.
30930 in base 35 = p8p and consists of only the digits '8' and 'p'.
30930 in base 41 = IGG and consists of only the digits 'G' and 'I'.
30930 in base 44 = Fgg and consists of only the digits 'F' and 'g'.
30930 in base 45 = FCF and consists of only the digits 'C' and 'F'.

The number 30930 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A064262: Values of m such that N=(am+1)(bm+1)(cm+1) is a Carmichael number, where a,b,c = 1,2,51.
A085467: Numerators of coefficients of e^2 in the table of (2n)th du Bois Reymond constants.
A138729: a(n) = -A085466(n) times the free coefficient of the 2n-th Du Bois-Reymond polynomial in e^2.
A214753: Number T(n,k) of solid standard Young tableaux of n cells and height = k; triangle T(n,k), n>=0, 0<=k<=n, read by rows.
A223034: Number of 3-vexillary permutations in S_n, that is, permutations whose Stanley symmetric function has at most 3 terms or at most 3 Edelman-Greene tableaux.
A273582: Number of solid standard Young tableaux of n cells and height two.

Thursday, May 2, 2019

Number of the day: 5866671398

Properties of the number 5866671398:

5866671398 = 2 × 7 × 113 × 347 × 10687 is the 5593050761th composite number and is squarefree.
5866671398 has 5 distinct prime factors, 32 divisors, 67 antidivisors and 2484623232 totatives.
5866671398 has a prime digit sum 59 in base 10.
Reversing the decimal digits of 5866671398 results in a sphenic number.
5866671398 is the difference of 2 positive pentagonal numbers in 8 ways.
5866671398 = 2862 + 6392 + 765912 is the sum of 3 positive squares.
58666713982 = 7787616902 + 58147539522 is the sum of 2 positive squares in 1 way.
58666713982 is the sum of 3 positive squares.
5866671398 is a proper divisor of 1861188916 - 1.

Wednesday, May 1, 2019

Number of the day: 838704

Properties of the number 838704:

838704 = 24 × 3 × 101 × 173 is the 771907th composite number and is not squarefree.
838704 has 4 distinct prime factors, 40 divisors, 15 antidivisors and 275200 totatives.
838704 has a sphenic digit sum 30 in base 10.
838704 has an oblong digit sum 30 in base 10.
838704 is the difference of 2 nonnegative squares in 12 ways.
838704 is the difference of 2 positive pentagonal numbers in 1 way.
838704 = 1482 + 1882 + 8842 is the sum of 3 positive squares.
8387042 = 4055042 + 7341602 = 1660802 + 8220962 = 887042 + 8340002 = 2520962 + 7999202 is the sum of 2 positive squares in 4 ways.
8387042 is the sum of 3 positive squares.
838704 is a proper divisor of 34720 - 1.
838704 in base 4 = 3030300300 and consists of only the digits '0' and '3'.

The number 838704 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A286879: Number of minimal dominating sets in the n-Andrasfai graph.

Tuesday, April 30, 2019

Number of the day: 28347

Carl Friedrich Gauss was born on this day 242 years ago.

Claude Shannon was born on this day 103 years ago.

Properties of the number 28347:

28347 = 3 × 11 × 859 is a sphenic number and squarefree.
28347 has 3 distinct prime factors, 8 divisors, 31 antidivisors and 17160 totatives.
28347 = 141742 - 141732 = 47262 - 47232 = 12942 - 12832 = 4462 - 4132 is the difference of 2 nonnegative squares in 4 ways.
28347 is the sum of 2 positive triangular numbers.
28347 is the difference of 2 positive pentagonal numbers in 2 ways.
28347 = 132 + 172 + 1672 is the sum of 3 positive squares.
283472 is the sum of 3 positive squares.
28347 is a proper divisor of 19796 - 1.
28347 = '283' + '47' is the concatenation of 2 prime numbers.
28347 is palindromic in (at least) the following bases: 2, 32, 41, 67, 74, -34, and -65.
28347 in base 32 = rlr and consists of only the digits 'l' and 'r'.
28347 in base 41 = GZG and consists of only the digits 'G' and 'Z'.
28347 in base 59 = 88R and consists of only the digits '8' and 'R'.

The number 28347 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A023609: Convolution of Fibonacci numbers and composite numbers.
A047661: Row 5 of square array defined in A047662.
A066897: Total number of odd parts in all partitions of n.
A270694: Alternating sum of centered heptagonal pyramidal numbers.

Monday, April 29, 2019

Number of the day: 999541962

Henri Poincaré was born on this day 165 years ago.

Properties of the number 999541962:

999541962 = 2 × 32 × 17 × 3266477 is the 948716359th composite number and is not squarefree.
999541962 has 4 distinct prime factors, 24 divisors, 23 antidivisors and 313581696 totatives.
999541962 = 2093 + 3933 + 9763 is the sum of 3 positive cubes in 1 way.
999541962 is the difference of 2 positive pentagonal numbers in 2 ways.
999541962 = 166292 + 268892 = 20192 + 315512 is the sum of 2 positive squares in 2 ways.
999541962 = 592 + 6402 + 316092 is the sum of 3 positive squares.
9995419622 = 4703726882 + 8819487902 = 1274029382 + 9913892402 = 4464946802 + 8942743622 = 5789504702 + 8148008882 is the sum of 2 positive squares in 4 ways.
9995419622 is the sum of 3 positive squares.
999541962 is a proper divisor of 179110728 - 1.
999541962 = '9995' + '41962' is the concatenation of 2 emirpimes.