56565681 has 24 divisors (see below), whose sum is σ = 81696384. Its totient is φ = 34794240.

The previous prime is 56565667. The next prime is 56565713. The reversal of 56565681 is 18656565.

It is not a de Polignac number, because 56565681 - 2⁶ = 56565617 is a prime.

It is a super-2 number, since 2×56565681² = 6399352533987522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (56565181) 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 23 ways as a sum of consecutive naturals, for example, 45336 + ... + 46566.

It is an arithmetic number, because the mean of its divisors is an integer number (3404016).

Almost surely, 2^56565681 is an apocalyptic number.

56565681 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

56565681 is a deficient number, since it is larger than the sum of its proper divisors (25130703).

56565681 is a wasteful number, since it uses less digits than its factorization.

56565681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1321 (or 1304 counting only the distinct ones).

The product of its digits is 216000, while the sum is 42.

The square root of 56565681 is about 7521.0159553082. The cubic root of 56565681 is about 383.8701478806.

The spelling of 56565681 in words is "fifty-six million, five hundred sixty-five thousand, six hundred eighty-one".