664858944 has 168 divisors, whose sum is σ = 2034032000. Its totient is φ = 207028224.

The previous prime is 664858921. The next prime is 664858951. The reversal of 664858944 is 449858466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 864192 + ... + 864960.

Almost surely, 2^664858944 is an apocalyptic number.

664858944 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664858944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1017016000).

664858944 is an abundant number, since it is smaller than the sum of its proper divisors (1369173056).

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

664858944 is a wasteful number, since it uses less digits than its factorization.

664858944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 885 (or 872 counting only the distinct ones).

The product of its digits is 6635520, while the sum is 54.

The square root of 664858944 is about 25784.8588128770. The cubic root of 664858944 is about 872.7901543707.

The spelling of 664858944 in words is "six hundred sixty-four million, eight hundred fifty-eight thousand, nine hundred forty-four".