56397235581 has 8 divisors (see below), whose sum is σ = 83551460160. Its totient is φ = 37598157036.

The previous prime is 56397235547. The next prime is 56397235639. The reversal of 56397235581 is 18553279365.

56397235581 is a `hidden beast` number, since 5 + 6 + 39 + 7 + 23 + 5 + 581 = 666.

It is not a de Polignac number, because 56397235581 - 2¹⁷ = 56397104509 is a prime.

It is a super-2 number, since 2×56397235581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56397235501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1044393225 + ... + 1044393278.

It is an arithmetic number, because the mean of its divisors is an integer number (10443932520).

Almost surely, 2^56397235581 is an apocalyptic number.

It is an amenable number.

56397235581 is a deficient number, since it is larger than the sum of its proper divisors (27154224579).

56397235581 is a wasteful number, since it uses less digits than its factorization.

56397235581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2088786512 (or 2088786506 counting only the distinct ones).

The product of its digits is 6804000, while the sum is 54.

The spelling of 56397235581 in words is "fifty-six billion, three hundred ninety-seven million, two hundred thirty-five thousand, five hundred eighty-one".