56815660 has 24 divisors (see below), whose sum is σ = 130160016. Its totient is φ = 20660160.

The previous prime is 56815651. The next prime is 56815667. The reversal of 56815660 is 6651865.

It is not an unprimeable number, because it can be changed into a prime (56815667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128907 + ... + 129346.

It is an arithmetic number, because the mean of its divisors is an integer number (5423334).

Almost surely, 2^56815660 is an apocalyptic number.

It is an amenable number.

56815660 is an abundant number, since it is smaller than the sum of its proper divisors (73344356).

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

56815660 is a wasteful number, since it uses less digits than its factorization.

56815660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258273 (or 258271 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 56815660 is about 7537.6163340940. The cubic root of 56815660 is about 384.4347921614.

It can be divided in two parts, 56815 and 660, that added together give a palindrome (57475).

The spelling of 56815660 in words is "fifty-six million, eight hundred fifteen thousand, six hundred sixty".