664804 has 12 divisors (see below), whose sum is σ = 1329664. Its totient is φ = 284904.

The previous prime is 664799. The next prime is 664843. The reversal of 664804 is 408466.

664804 is an admirable number.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (28), and also a Moran number because the ratio is a prime number: 23743 = 664804 / (6 + 6 + 4 + 8 + 0 + 4).

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, 11844 + ... + 11899.

2⁶⁶⁴⁸⁰⁴ is an apocalyptic number.

It is an amenable number.

664804 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

664804 is a wasteful number, since it uses less digits than its factorization.

664804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23754 (or 23752 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 664804 is about 815.3551373481. The cubic root of 664804 is about 87.2766111224.

The spelling of 664804 in words is "six hundred sixty-four thousand, eight hundred four".