56505568681 has 9 divisors (see below), whose sum is σ = 59640838173. Its totient is φ = 53527312620.

The previous prime is 56505568661. The next prime is 56505568687. The reversal of 56505568681 is 18686550565.

The square root of 56505568681 is 237709.

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

It is not a de Polignac number, because 56505568681 - 2²⁷ = 56371350953 is a prime.

It is a super-2 number, since 2×56505568681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56505568687) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4510216 + ... + 4522726.

It is an arithmetic number, because the mean of its divisors is an integer number (6626759797).

Almost surely, 2^56505568681 is an apocalyptic number.

56505568681 is the 237709-th square number.

56505568681 is the 118855-th centered octagonal number.

It is an amenable number.

56505568681 is a deficient number, since it is larger than the sum of its proper divisors (3135269492).

56505568681 is an frugal number, since it uses more digits than its factorization.

56505568681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25060 (or 12530 counting only the distinct ones).

The product of its (nonzero) digits is 8640000, while the sum is 55.

The spelling of 56505568681 in words is "fifty-six billion, five hundred five million, five hundred sixty-eight thousand, six hundred eighty-one".