15556469100561 has 15 divisors (see below), whose sum is σ = 23238729091083. Its totient is φ = 10370955735360.

The previous prime is 15556469100551. The next prime is 15556469100569. The reversal of 15556469100561 is 16500196465551.

The square root of 15556469100561 is 3944169.

It is a perfect power (a square), and thus also a powerful number.

15556469100561 is a `hidden beast` number, since 1 + 5 + 5 + 5 + 6 + 4 + 69 + 10 + 0 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 14275407314961 + 1281061785600 = 3778281^2 + 1131840^2 .

It is not a de Polignac number, because 15556469100561 - 2⁷ = 15556469100433 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 15556469100498 and 15556469100507.

It is not an unprimeable number, because it can be changed into a prime (15556469100569) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 35278401 + ... + 35716641.

Almost surely, 2^{15556469100561} is an apocalyptic number.

15556469100561 is the 3944169-th square number.

15556469100561 is the 1972085-th centered octagonal number.

It is an amenable number.

15556469100561 is a deficient number, since it is larger than the sum of its proper divisors (7682259990522).

15556469100561 is an frugal number, since it uses more digits than its factorization.

15556469100561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876494 (or 438244 counting only the distinct ones).

The product of its (nonzero) digits is 4860000, while the sum is 54.

The spelling of 15556469100561 in words is "fifteen trillion, five hundred fifty-six billion, four hundred sixty-nine million, one hundred thousand, five hundred sixty-one".