664879624 has 8 divisors (see below), whose sum is σ = 1246649310. Its totient is φ = 332439808.

The previous prime is 664879609. The next prime is 664879637. The reversal of 664879624 is 426978466.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 664711524 + 168100 = 25782^2 + 410^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41554969 + ... + 41554984.

Almost surely, 2^664879624 is an apocalyptic number.

It is an amenable number.

664879624 is a deficient number, since it is larger than the sum of its proper divisors (581769686).

664879624 is a wasteful number, since it uses less digits than its factorization.

664879624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83109959 (or 83109955 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 52.

The square root of 664879624 is about 25785.2598202927. The cubic root of 664879624 is about 872.7992034647.

The spelling of 664879624 in words is "six hundred sixty-four million, eight hundred seventy-nine thousand, six hundred twenty-four".