56115565561 has 16 divisors (see below), whose sum is σ = 64514324160. Its totient is φ = 48272647680.

The previous prime is 56115565553. The next prime is 56115565567. The reversal of 56115565561 is 16556551165.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 56115565561 - 2³ = 56115565553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (56115565567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22465 + ... + 335761.

It is an arithmetic number, because the mean of its divisors is an integer number (4032145260).

Almost surely, 2^56115565561 is an apocalyptic number.

It is an amenable number.

56115565561 is a deficient number, since it is larger than the sum of its proper divisors (8398758599).

56115565561 is a wasteful number, since it uses less digits than its factorization.

56115565561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314184.

The product of its digits is 675000, while the sum is 46.

The spelling of 56115565561 in words is "fifty-six billion, one hundred fifteen million, five hundred sixty-five thousand, five hundred sixty-one".