56581920 has 72 divisors (see below), whose sum is σ = 193090716. Its totient is φ = 15088128.

The previous prime is 56581919. The next prime is 56581939. The reversal of 56581920 is 2918565.

It is a happy number.

56581920 is a `hidden beast` number, since 56 + 581 + 9 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 54110736 + 2471184 = 7356^2 + 1572^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18207 + ... + 21086.

Almost surely, 2^56581920 is an apocalyptic number.

It is an amenable number.

56581920 is an abundant number, since it is smaller than the sum of its proper divisors (136508796).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

56581920 is a wasteful number, since it uses less digits than its factorization.

56581920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39314 (or 39303 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 56581920 is about 7522.0954527312. The cubic root of 56581920 is about 383.9068784611.

The spelling of 56581920 in words is "fifty-six million, five hundred eighty-one thousand, nine hundred twenty".