56317581 has 6 divisors (see below), whose sum is σ = 81347630. Its totient is φ = 37545048.

The previous prime is 56317561. The next prime is 56317601. The reversal of 56317581 is 18571365.

56317581 is a `hidden beast` number, since 5 + 63 + 17 + 581 = 666.

It is an interprime number because it is at equal distance from previous prime (56317561) and next prime (56317601).

It can be written as a sum of positive squares in only one way, i.e., 56115081 + 202500 = 7491^2 + 450^2 .

It is not a de Polignac number, because 56317581 - 2⁹ = 56317069 is a prime.

It is a super-2 number, since 2×56317581² = 6343339859383122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56317511) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3128746 + ... + 3128763.

Almost surely, 2^56317581 is an apocalyptic number.

It is an amenable number.

56317581 is a deficient number, since it is larger than the sum of its proper divisors (25030049).

56317581 is a wasteful number, since it uses less digits than its factorization.

56317581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6257515 (or 6257512 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 56317581 is about 7504.5040475704. The cubic root of 56317581 is about 383.3081005865.

The spelling of 56317581 in words is "fifty-six million, three hundred seventeen thousand, five hundred eighty-one".