656904 has 32 divisors (see below), whose sum is σ = 1664640. Its totient is φ = 216000.

The previous prime is 656891. The next prime is 656917. The reversal of 656904 is 409656.

656904 = T₁₄ + T₁₅ + ... + T₁₅₇.

It is an interprime number because it is at equal distance from previous prime (656891) and next prime (656917).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2289 + ... + 2559.

It is an arithmetic number, because the mean of its divisors is an integer number (52020).

2⁶⁵⁶⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

656904 is an abundant number, since it is smaller than the sum of its proper divisors (1007736).

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

656904 is a wasteful number, since it uses less digits than its factorization.

656904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 656904 is about 810.4961443462. The cubic root of 656904 is about 86.9295241116.

The spelling of 656904 in words is "six hundred fifty-six thousand, nine hundred four".