656506605666 has 32 divisors (see below), whose sum is σ = 1322157066048. Its totient is φ = 217316736000.

The previous prime is 656506605647. The next prime is 656506605719. The reversal of 656506605666 is 666506605656.

656506605666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139255 + ... + 1154298.

It is an arithmetic number, because the mean of its divisors is an integer number (41317408314).

Almost surely, 2^656506605666 is an apocalyptic number.

656506605666 is an abundant number, since it is smaller than the sum of its proper divisors (665650460382).

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

656506605666 is a wasteful number, since it uses less digits than its factorization.

656506605666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1294146.

The product of its (nonzero) digits is 34992000, while the sum is 57.

The spelling of 656506605666 in words is "six hundred fifty-six billion, five hundred six million, six hundred five thousand, six hundred sixty-six".