664920 has 48 divisors (see below), whose sum is σ = 2162160. Its totient is φ = 177216.

The previous prime is 664891. The next prime is 664933. The reversal of 664920 is 29466.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 664920.

It is an unprimeable number.

664920 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 564 + ... + 1283.

It is an arithmetic number, because the mean of its divisors is an integer number (45045).

2⁶⁶⁴⁹²⁰ is an apocalyptic number.

664920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

664920 is an abundant number, since it is smaller than the sum of its proper divisors (1497240).

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

664920 is a wasteful number, since it uses less digits than its factorization.

664920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1864 (or 1857 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 664920 is about 815.4262688925. The cubic root of 664920 is about 87.2816870536.

The spelling of 664920 in words is "six hundred sixty-four thousand, nine hundred twenty".