56661660 has 96 divisors (see below), whose sum is σ = 192326400. Its totient is φ = 13734720.

The previous prime is 56661643. The next prime is 56661691. The reversal of 56661660 is 6616665.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1171 + ... + 10709.

It is an arithmetic number, because the mean of its divisors is an integer number (2003400).

Almost surely, 2^56661660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56661660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96163200).

56661660 is an abundant number, since it is smaller than the sum of its proper divisors (135664740).

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

56661660 is a wasteful number, since it uses less digits than its factorization.

56661660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9568 (or 9560 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 56661660 is about 7527.3939713556. The cubic root of 56661660 is about 384.0871384279.

It can be divided in two parts, 566 and 61660, that added together give a palindrome (62226).

The spelling of 56661660 in words is "fifty-six million, six hundred sixty-one thousand, six hundred sixty".