664404 has 24 divisors (see below), whose sum is σ = 1669920. Its totient is φ = 204384.

The previous prime is 664403. The next prime is 664421. The reversal of 664404 is 404466.

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1974 + ... + 2285.

It is an arithmetic number, because the mean of its divisors is an integer number (69580).

2⁶⁶⁴⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

664404 is an abundant number, since it is smaller than the sum of its proper divisors (1005516).

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

664404 is a wasteful number, since it uses less digits than its factorization.

664404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4279 (or 4277 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 664404 is about 815.1098085534. The cubic root of 664404 is about 87.2591033815.

The spelling of 664404 in words is "six hundred sixty-four thousand, four hundred four".