656664 has 16 divisors (see below), whose sum is σ = 1641720. Its totient is φ = 218880.

The previous prime is 656657. The next prime is 656671. The reversal of 656664 is 466656.

It is an interprime number because it is at equal distance from previous prime (656657) and next prime (656671).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13657 + ... + 13704.

2⁶⁵⁶⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

656664 is an abundant number, since it is smaller than the sum of its proper divisors (985056).

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

656664 is a wasteful number, since it uses less digits than its factorization.

656664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27370 (or 27366 counting only the distinct ones).

The product of its digits is 25920, while the sum is 33.

The square root of 656664 is about 810.3480733611. The cubic root of 656664 is about 86.9189362494.

The spelling of 656664 in words is "six hundred fifty-six thousand, six hundred sixty-four".