Sunday, July 31, 2022

Number of the day: 629046

Properties of the number 629046:

629046 = 2 × 34 × 11 × 353 is the 577774th composite number and is not squarefree.
629046 has 4 distinct prime factors, 40 divisors, 23 antidivisors and 190080 totatives.
629046 = 12 + 142 + 7932 is the sum of 3 positive squares.
6290462 = 4009502 + 4847042 is the sum of 2 positive squares in 1 way.
6290462 is the sum of 3 positive squares.
629046 is a proper divisor of 647160 - 1.
629046 = '62' + '9046' is the concatenation of 2 semiprime numbers.

Saturday, July 30, 2022

Number of the day: 202917

Properties of the number 202917:

202917 = 3 × 112 × 13 × 43 is the 184699th composite number and is not squarefree.
202917 has 4 distinct prime factors, 24 divisors, 31 antidivisors and 110880 totatives.
202917 has a semiprime digit sum 21 in base 10.
202917 has a Fibonacci digit sum 21 in base 10.
202917 has a triangular digit sum 21 in base 10.
202917 is the difference of 2 nonnegative squares in 12 ways.
202917 is the sum of 2 positive triangular numbers.
202917 is the difference of 2 positive pentagonal numbers in 5 ways.
202917 = 22 + 472 + 4482 is the sum of 3 positive squares.
2029172 = 780452 + 1873082 is the sum of 2 positive squares in 1 way.
2029172 is the sum of 3 positive squares.
202917 is a proper divisor of 72714 - 1.
202917 = '2029' + '17' is the concatenation of 2 prime numbers.
202917 = '202' + '917' is the concatenation of 2 semiprime numbers.
202917 is palindromic in (at least) the following bases: -60, and -62.
202917 in base 32 = 6655 and consists of only the digits '5' and '6'.
202917 in base 34 = 55i5 and consists of only the digits '5' and 'i'.

The number 202917 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A218266: Number of standard Young tableaux of n cells and height >= 6.

Thursday, July 28, 2022

Number of the day: 7793

Properties of the number 7793:

7793 is a cyclic number.
7793 is the 987th prime.
7793 has 13 antidivisors and 7792 totatives.
7793 has an emirpimes digit sum 26 in base 10.
Reversing the decimal digits of 7793 results in a semiprime.
7793 = 38972 - 38962 is the difference of 2 nonnegative squares in 1 way.
7793 is the difference of 2 positive pentagonal numbers in 1 way.
7793 = 72 + 882 is the sum of 2 positive squares in 1 way.
7793 = 62 + 192 + 862 is the sum of 3 positive squares.
77932 = 12322 + 76952 is the sum of 2 positive squares in 1 way.
77932 is the sum of 3 positive squares.
7793 is a proper divisor of 43487 - 1.
7793 = '77' + '93' is the concatenation of 2 semiprime numbers.
7793 is an emirp in (at least) the following bases: 3, 4, 5, 11, 16, 20, 21, 23, 24, 27, 31, 41, 49, 55, 59, 61, 63, 64, 67, 70, 80, 83, 84, 85, 86, 95, 98, and 100.
7793 is palindromic in (at least) the following bases: 28, 53, -34, and -44.
7793 in base 28 = 9q9 and consists of only the digits '9' and 'q'.
7793 in base 33 = 755 and consists of only the digits '5' and '7'.
7793 in base 52 = 2jj and consists of only the digits '2' and 'j'.
7793 in base 53 = 2f2 and consists of only the digits '2' and 'f'.

The number 7793 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A001134: Primes p such that the multiplicative order of 2 modulo p is (p-1)/4.
A051026: Number of primitive subsequences of {1, 2, ..., n}.
A057622: Initial prime in first sequence of n consecutive primes congruent to 5 modulo 6.
A068652: Numbers such that every cyclic permutation is a prime.
A128337: Numbers k such that (7^k + 5^k)/12 is prime.
A142200: Primes congruent to 3 mod 41.
A154577: Primes of the form 2n^2+14n+5.
A293663: Circular primes that are not repunits.
A316652: Number of series-reduced rooted trees whose leaves span an initial interval of positive integers with multiplicities an integer partition of n.
A317716: Square array A(n, k), read by antidiagonals downwards: k-th prime p such that cyclic digit shifts produce exactly n different primes.

Wednesday, July 27, 2022

Number of the day: 75335

Ernst Friedrich Ferdinand Zermelo was born on this day 151 years ago.

Properties of the number 75335:

75335 = 5 × 13 × 19 × 61 is the 67912th composite number and is squarefree.
75335 has 4 distinct prime factors, 16 divisors, 21 antidivisors and 51840 totatives.
75335 has a prime digit sum 23 in base 10.
Reversing the decimal digits of 75335 results in a semiprime.
75335 = 376682 - 376672 = 75362 - 75312 = 29042 - 28912 = 19922 - 19732 = 6482 - 5872 = 6122 - 5472 = 4442 - 3492 = 2762 - 292 is the difference of 2 nonnegative squares in 8 ways.
75335 is the difference of 2 positive pentagonal numbers in 7 ways.
75335 is not the sum of 3 positive squares.
753352 = 452012 + 602682 = 335922 + 674312 = 511292 + 553282 = 185442 + 730172 = 50732 + 751642 = 314072 + 684762 = 382472 + 649042 = 259162 + 707372 = 493242 + 569432 = 289752 + 695402 = 159602 + 736252 = 410402 + 631752 = 135852 + 741002 is the sum of 2 positive squares in 13 ways.
753352 is the sum of 3 positive squares.
75335 is a proper divisor of 155910 - 1.
75335 = '753' + '35' is the concatenation of 2 semiprime numbers.
75335 is palindromic in (at least) base 70.
75335 in base 58 = MMp and consists of only the digits 'M' and 'p'.

The number 75335 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A132124: a(n) = n*(n+1)*(8*n + 1)/6.
A137080: Numbers k such that k and k^2 use only the digits 2, 3, 5, 6 and 7.
A345705: Numbers k such that (3^ord(3/2, k) - 2^ord(3/2, k))/k is a prime, where ord(3/2, k) is the multiplicative order of 3/2 (mod k).

Tuesday, July 26, 2022

Number of the day: 3430

Properties of the number 3430:

3430 = 2 × 5 × 73 is the 2949th composite number and is not squarefree.
3430 has 3 distinct prime factors, 16 divisors, 11 antidivisors and 1176 totatives.
3430 has a semiprime digit sum 10 in base 10.
3430 has a triangular digit sum 10 in base 10.
3430 = 73 + 73 + 143 is the sum of 3 positive cubes in 1 way.
3430 is the sum of 2 positive triangular numbers.
3430 is the difference of 2 positive pentagonal numbers in 4 ways.
3430 = 92 + 102 + 572 is the sum of 3 positive squares.
34302 = 20582 + 27442 is the sum of 2 positive squares in 1 way.
34302 is the sum of 3 positive squares.
3430 is a proper divisor of 13734 - 1.
3430 is palindromic in (at least) the following bases: 18, 21, 25, 69, 97, and -19.
3430 in base 16 = d66 and consists of only the digits '6' and 'd'.
3430 in base 18 = aaa and consists of only the digit 'a'.
3430 in base 19 = 99a and consists of only the digits '9' and 'a'.
3430 in base 21 = 7g7 and consists of only the digits '7' and 'g'.
3430 in base 24 = 5mm and consists of only the digits '5' and 'm'.
3430 in base 25 = 5c5 and consists of only the digits '5' and 'c'.
3430 in base 58 = 118 and consists of only the digits '1' and '8'.

The number 3430 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A007727: Number of 2n-bead black-white strings with n black beads and fundamental period 2n.
A025632: Numbers of form 7^i*10^j, with i, j >= 0.
A027466: Triangle whose (i,j)-th entry is binomial(i,j)*7^(i-j).
A027474: a(n) = 7^(n-2) * C(n,2).
A051682: 11-gonal (or hendecagonal) numbers: a(n) = n*(9*n-7)/2.
A088409: a(n) = A063416(n)/7.
A208688: T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 0 1 vertically
A241638: Number of partitions p of n such that (number of even numbers in p) = (number of odd numbers in p).
A325793: Positive integers whose number of divisors is equal to their sum of prime indices.
A351255: Numbers whose k-th arithmetic derivative is zero for some k>0, ordered by their position in A276086.

Monday, July 25, 2022

Number of the day: 545083

Properties of the number 545083:

545083 is a cyclic number.
545083 = 7 × 11 × 7079 is a sphenic number and squarefree.
545083 has 3 distinct prime factors, 8 divisors, 19 antidivisors and 424680 totatives.
545083 has a semiprime digit sum 25 in base 10.
545083 = 2725422 - 2725412 = 389382 - 389312 = 247822 - 247712 = 35782 - 35012 is the difference of 2 nonnegative squares in 4 ways.
545083 is the sum of 2 positive triangular numbers.
545083 is the difference of 2 positive pentagonal numbers in 4 ways.
545083 = 852 + 1232 + 7232 is the sum of 3 positive squares.
5450832 is the sum of 3 positive squares.
545083 is a proper divisor of 437078 - 1.
545083 = '5' + '45083' is the concatenation of 2 prime numbers.

The number 545083 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A174728: Triangle read by rows: T(n, m, q) = (1-q^n)*Eulerian(n+1, m) - (1-q^n) + 1, with q = 2.

Sunday, July 24, 2022

Number of the day: 165801

Charles Émile Picard was born on this day 166 years ago.

Properties of the number 165801:

165801 is a cyclic number.
165801 = 3 × 17 × 3251 is a sphenic number and squarefree.
165801 has 3 distinct prime factors, 8 divisors, 9 antidivisors and 104000 totatives.
165801 has a semiprime digit sum 21 in base 10.
165801 has a Fibonacci digit sum 21 in base 10.
165801 has a triangular digit sum 21 in base 10.
Reversing the decimal digits of 165801 results in a semiprime.
165801 = 829012 - 829002 = 276352 - 276322 = 48852 - 48682 = 16512 - 16002 is the difference of 2 nonnegative squares in 4 ways.
165801 is the difference of 2 positive pentagonal numbers in 2 ways.
165801 = 52 + 762 + 4002 is the sum of 3 positive squares.
1658012 = 780242 + 1462952 is the sum of 2 positive squares in 1 way.
1658012 is the sum of 3 positive squares.
165801 is a proper divisor of 123720 - 1.
165801 is palindromic in (at least) the following bases: 50, -64, and -90.
165801 in base 50 = 1GG1 and consists of only the digits '1' and 'G'.

The number 165801 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A005904: Centered dodecahedral numbers.

Friday, July 22, 2022

Number of the day: 7222022

Happy Casual π Day!

Properties of the number 7222022:

7222022 = 2 × 43 × 79 × 1063 is the 6731307th composite number and is squarefree.
7222022 has 4 distinct prime factors, 16 divisors, 27 antidivisors and 3479112 totatives.
7222022 has an emirp digit sum 17 in base 10.
7222022 = 172 + 422 + 26872 is the sum of 3 positive squares.
72220222 is the sum of 3 positive squares.
7222022 is a proper divisor of 7234 - 1.

Thursday, July 21, 2022

Number of the day: 763856

Properties of the number 763856:

763856 = 24 × 47741 is the 702587th composite number and is not squarefree.
763856 has 2 distinct prime factors, 10 divisors, 9 antidivisors and 381920 totatives.
763856 has a semiprime digit sum 35 in base 10.
Reversing the decimal digits of 763856 results in a prime.
763856 = 1909652 - 1909632 = 954842 - 954802 = 477452 - 477372 is the difference of 2 nonnegative squares in 3 ways.
763856 is the difference of 2 positive pentagonal numbers in 1 way.
763856 = 6162 + 6202 is the sum of 2 positive squares in 1 way.
763856 = 562 + 2042 + 8482 is the sum of 3 positive squares.
7638562 = 49442 + 7638402 is the sum of 2 positive squares in 1 way.
7638562 is the sum of 3 positive squares.
763856 is a proper divisor of 1163140 - 1.
763856 = '76385' + '6' is the concatenation of 2 semiprime numbers.

Wednesday, July 20, 2022

Number of the day: 258031

Properties of the number 258031:

258031 is a cyclic number.
258031 is the 22678th prime.
258031 has 17 antidivisors and 258030 totatives.
258031 has a prime digit sum 19 in base 10.
258031 = 1290162 - 1290152 is the difference of 2 nonnegative squares in 1 way.
258031 is the difference of 2 positive pentagonal numbers in 1 way.
258031 is not the sum of 3 positive squares.
2580312 is the sum of 3 positive squares.
258031 is a proper divisor of 919141 - 1.
258031 = '2' + '58031' is the concatenation of 2 prime numbers.
258031 = '25' + '8031' is the concatenation of 2 semiprime numbers.
258031 is an emirp in (at least) the following bases: 2, 9, 16, 19, 21, 22, 27, 28, 29, 31, 33, 45, 47, 52, 56, 60, 61, 63, 65, 66, 72, 74, 77, 79, 90, 91, 94, and 95.
258031 is palindromic in (at least) the following bases: 4, and -73.
258031 in base 4 = 332333233 and consists of only the digits '2' and '3'.

The number 258031 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A224605: Number of (n+2) X 9 0..2 matrices with each 3 X 3 subblock idempotent.
A254905: Number of (n+2)X(6+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally
A254907: T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally
A254908: Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally

Tuesday, July 19, 2022

Number of the day: 23823322

Properties of the number 23823322:

23823322 = 2 × 1123 × 10607 is a sphenic number and squarefree.
23823322 has 3 distinct prime factors, 8 divisors, 11 antidivisors and 11899932 totatives.
23823322 has a semiprime digit sum 25 in base 10.
23823322 is the difference of 2 positive pentagonal numbers in 3 ways.
23823322 = 242 + 2392 + 48752 is the sum of 3 positive squares.
238233222 is the sum of 3 positive squares.
23823322 is a proper divisor of 85758333 - 1.
23823322 = '238233' + '22' is the concatenation of 2 semiprime numbers.
23823322 = '2382' + '3322' is the concatenation of 2 sphenic numbers.

Monday, July 18, 2022

Number of the day: 72737033

Properties of the number 72737033:

72737033 is a cyclic number.
72737033 = 17 × 4278649 is semiprime and squarefree.
72737033 has 2 distinct prime factors, 4 divisors, 37 antidivisors and 68458368 totatives.
Reversing the decimal digits of 72737033 results in an emirpimes.
72737033 = 363685172 - 363685162 = 21393332 - 21393162 is the difference of 2 nonnegative squares in 2 ways.
72737033 is the difference of 2 positive pentagonal numbers in 2 ways.
72737033 = 22482 + 82272 = 18882 + 83172 is the sum of 2 positive squares in 2 ways.
72737033 = 262 + 2092 + 85262 is the sum of 3 positive squares.
727370332 = 369885922 + 626300252 = 342291922 + 641797352 = 314049922 + 656079452 = 31640402 + 726681832 is the sum of 2 positive squares in 4 ways.
727370332 is the sum of 3 positive squares.
72737033 is a proper divisor of 193113648 - 1.
72737033 = '7273' + '7033' is the concatenation of 2 semiprime numbers.
72737033 is an emirpimes in (at least) the following bases: 6, 7, 10, 11, 14, 17, 20, 22, 27, 31, 33, 36, 37, 45, 47, 48, 49, 55, 56, 63, 68, 70, 75, 78, 82, 83, 84, 87, 89, 90, 95, 97, and 99.

Sunday, July 17, 2022

Number of the day: 7172022

Happy Yellow Pig Day!

Properties of the number 7172022:

7172022 = 2 × 3 × 11 × 132 × 643 is the 6684450th composite number and is not squarefree.
7172022 has 5 distinct prime factors, 48 divisors, 27 antidivisors and 2003040 totatives.
7172022 has a semiprime digit sum 21 in base 10.
7172022 has a Fibonacci digit sum 21 in base 10.
7172022 has a triangular digit sum 21 in base 10.
Reversing the decimal digits of 7172022 results in a sphenic number.
7172022 is the sum of 2 positive triangular numbers.
7172022 is the difference of 2 positive pentagonal numbers in 7 ways.
7172022 = 432 + 622 + 26772 is the sum of 3 positive squares.
71720222 = 27584702 + 66203282 = 50501222 + 50925602 is the sum of 2 positive squares in 2 ways.
71720222 is the sum of 3 positive squares.
7172022 is a proper divisor of 1109390 - 1.
7172022 in base 3 = 111111101011110 and consists of only the digits '0' and '1'.

Saturday, July 16, 2022

Number of the day: 250162601912

Properties of the number 250162601912:

250162601912 = 23 × 31 × 97 × 10399177 is composite and not squarefree.
250162601912 has 4 distinct prime factors, 32 divisors, 31 antidivisors and 119798507520 totatives.
250162601912 has a semiprime digit sum 35 in base 10.
250162601912 = 6843 + 29363 + 60783 = 38063 + 42403 + 49163 is the sum of 3 positive cubes in 2 ways.
250162601912 = 625406504792 - 625406504772 = 312703252412 - 312703252372 = 20174403692 - 20174403072 = 10087202312 - 10087201072 = 6447490712 - 6447488772 = 3223746812 - 3223742932 = 208013612 - 207953472 = 104051912 - 103931632 is the difference of 2 nonnegative squares in 8 ways.
250162601912 = 4662 + 35162 + 5001502 is the sum of 3 positive squares.
2501626019122 = 1686187910402 + 1847945635122 = 1676347332402 + 1856877045122 = 1489057176882 + 2010184435202 = 241751253122 + 2489917482802 is the sum of 2 positive squares in 4 ways.
2501626019122 is the sum of 3 positive squares.
250162601912 is a proper divisor of 1297866598 - 1.

Friday, July 15, 2022

Number of the day: 180293

Properties of the number 180293:

180293 is a cyclic number.
180293 = 29 × 6217 is semiprime and squarefree.
180293 has 2 distinct prime factors, 4 divisors, 19 antidivisors and 174048 totatives.
180293 has a prime digit sum 23 in base 10.
Reversing the decimal digits of 180293 results in an emirpimes.
180293 = 901472 - 901462 = 31232 - 30942 is the difference of 2 nonnegative squares in 2 ways.
180293 is the difference of 2 positive pentagonal numbers in 2 ways.
180293 is the difference of 2 positive pentagonal pyramidal numbers in 1 way.
180293 = 2572 + 3382 = 472 + 4222 is the sum of 2 positive squares in 2 ways.
180293 = 402 + 632 + 4182 is the sum of 3 positive squares.
1802932 = 1243402 + 1305572 = 481952 + 1737322 = 396682 + 1758752 = 925682 + 1547152 is the sum of 2 positive squares in 4 ways.
1802932 is the sum of 3 positive squares.
180293 is a proper divisor of 115114 - 1.
180293 is an emirpimes in (at least) the following bases: 4, 5, 7, 8, 9, 10, 13, 15, 21, 23, 24, 26, 29, 31, 34, 35, 36, 40, 42, 44, 45, 48, 49, 50, 51, 52, 55, 57, 59, 69, 75, 77, 82, 83, 92, 95, and 97.
180293 is palindromic in (at least) the following bases: -90, and -91.

The number 180293 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A146422: Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1010-1111 pattern in any orientation.

Thursday, July 14, 2022

Number of the day: 90251429

Properties of the number 90251429:

90251429 is a cyclic number.
90251429 = 89 × 1014061 is semiprime and squarefree.
90251429 has 2 distinct prime factors, 4 divisors, 19 antidivisors and 89237280 totatives.
Reversing the decimal digits of 90251429 results in a prime.
90251429 = 451257152 - 451257142 = 5070752 - 5069862 is the difference of 2 nonnegative squares in 2 ways.
90251429 is the difference of 2 positive pentagonal numbers in 2 ways.
90251429 = 53902 + 78232 = 46702 + 82732 is the sum of 2 positive squares in 2 ways.
90251429 = 232 + 302 + 95002 is the sum of 3 positive squares.
902514292 = 466336292 + 772698202 = 395483792 + 811248802 = 321472292 + 843319402 = 80580602 + 898909792 is the sum of 2 positive squares in 4 ways.
902514292 is the sum of 3 positive squares.
90251429 is a proper divisor of 130167604 - 1.
90251429 is an emirpimes in (at least) the following bases: 11, 15, 17, 25, 26, 33, 34, 35, 38, 41, 42, 45, 47, 49, 57, 58, 70, 71, 73, 74, 75, 79, 82, 84, 85, 87, 88, 90, 94, 95, and 98.