56997479891 has 16 divisors (see below), whose sum is σ = 62447631360. Its totient is φ = 51592554720.

The previous prime is 56997479857. The next prime is 56997479893. The reversal of 56997479891 is 19897479965.

It is a cyclic number.

It is not a de Polignac number, because 56997479891 - 2¹⁸ = 56997217747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56997479893) 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, 2544446 + ... + 2566748.

It is an arithmetic number, because the mean of its divisors is an integer number (3902976960).

Almost surely, 2^56997479891 is an apocalyptic number.

56997479891 is a deficient number, since it is larger than the sum of its proper divisors (5450151469).

56997479891 is a wasteful number, since it uses less digits than its factorization.

56997479891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23306.

The product of its digits is 308629440, while the sum is 74.

Adding to 56997479891 its sum of digits (74), we get a palindrome (56997479965).

The spelling of 56997479891 in words is "fifty-six billion, nine hundred ninety-seven million, four hundred seventy-nine thousand, eight hundred ninety-one".