56577533581 has 2 divisors, whose sum is σ = 56577533582. Its totient is φ = 56577533580.

The previous prime is 56577533501. The next prime is 56577533681. The reversal of 56577533581 is 18533577565.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43917908356 + 12659625225 = 209566^2 + 112515^2 .

It is a cyclic number.

It is not a de Polignac number, because 56577533581 - 2³⁵ = 22217795213 is a prime.

It is a super-2 number, since 2×56577533581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56577533501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28288766790 + 28288766791.

It is an arithmetic number, because the mean of its divisors is an integer number (28288766791).

Almost surely, 2^56577533581 is an apocalyptic number.

It is an amenable number.

56577533581 is a deficient number, since it is larger than the sum of its proper divisors (1).

56577533581 is an equidigital number, since it uses as much as digits as its factorization.

56577533581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13230000, while the sum is 55.

The spelling of 56577533581 in words is "fifty-six billion, five hundred seventy-seven million, five hundred thirty-three thousand, five hundred eighty-one".