## Johann Bernoulli was born on this day 349 years ago.

### Properties of the number 8939:

8939 = 7 × 1277 is semiprime and squarefree.8939 has 2 distinct prime factors, 4 divisors, 11 antidivisors and 7656 totatives.

8939 has a prime digit sum 29 in base 10.

Reversing the decimal digits of 8939 results in a sphenic number.

8939 = (47 × 48)/2 + … + (53 × 54)/2 is the sum of at least 2 consecutive triangular numbers in 1 way.

8939 = 4470

^{2}- 4469

^{2}= 642

^{2}- 635

^{2}is the difference of 2 nonnegative squares in 2 ways.

8939 is the sum of 2 positive triangular numbers.

8939 is the difference of 2 positive pentagonal numbers in 2 ways.

8939 = 17

^{2}+ 27

^{2}+ 89

^{2}is the sum of 3 positive squares.

8939

^{2}= 5236

^{2}+ 7245

^{2}is the sum of 2 positive squares in 1 way.

8939

^{2}is the sum of 3 positive squares.

8939 is a divisor of 113

^{4}- 1.

8939 = '893' + '9' is the concatenation of 2 semiprime numbers.

8939 is an emirpimes in (at least) the following bases: 2, 3, 4, 5, 6, 7, 9, 11, 13, 14, 16, 17, 19, 20, 23, 24, 26, 34, 37, 41, 42, 43, 49, 52, 53, 55, 56, 57, 61, 65, 69, 72, 74, 76, 79, 84, 86, 88, 91, 94, 95, 96, and 98.

8939 is palindromic in (at least) the following bases: 25, 82, and -9.

8939 in base 25 = e7e and consists of only the digits '7' and 'e'.

8939 in base 28 = bb7 and consists of only the digits '7' and 'b'.

8939 in base 31 = 99b and consists of only the digits '9' and 'b'.

8939 in base 54 = 33T and consists of only the digits '3' and 'T'.

### The number 8939 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.A017822: Expansion of 1/(1-x^3-x^4-x^5-x^6-x^7-x^8-x^9).

A041469: Denominators of continued fraction convergents to sqrt(250).

A042937: Denominators of continued fraction convergents to sqrt(1000).

A058366: Number of ways to cover (without overlapping) a ring lattice (necklace) of n sites with molecules that are 7 sites wide.

A069833: Prefixing, suffixing or inserting a 9 in the number anywhere gives a prime.

A089141: Square array, read by antidiagonal: T(n,k) = n*T(n,k-1)+(-1)^k*T(n,floor(k/2)).

A173893: (Average of twin balanced prime pairs)/10.

A184699: Number of strings of numbers x(i=1..n) in 0..5 with sum i*x(i) equal to n*5

A184709: Number of strings of numbers x(i=1..9) in 0..n with sum i*x(i) equal to n*9

A271695: Partial sums of the number of active (ON,black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 398", based on the 5-celled von Neumann neighborhood.

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