664791028 has 12 divisors (see below), whose sum is σ = 1269146592. Its totient is φ = 302177720.

The previous prime is 664791013. The next prime is 664791037. The reversal of 664791028 is 820197466.

It is a super-2 number, since 2×664791028² = 883894221818593568, which contains 22 as substring.

It is a congruent number.

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, 7554400 + ... + 7554487.

It is an arithmetic number, because the mean of its divisors is an integer number (105762216).

Almost surely, 2^664791028 is an apocalyptic number.

It is an amenable number.

664791028 is a deficient number, since it is larger than the sum of its proper divisors (604355564).

664791028 is a wasteful number, since it uses less digits than its factorization.

664791028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15108902 (or 15108900 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 664791028 is about 25783.5418048025. The cubic root of 664791028 is about 872.7604345656.

The spelling of 664791028 in words is "six hundred sixty-four million, seven hundred ninety-one thousand, twenty-eight".