664025664 has 56 divisors (see below), whose sum is σ = 1759252768. Its totient is φ = 221045760.

The previous prime is 664025639. The next prime is 664025683. The reversal of 664025664 is 466520466.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178059 + ... + 181749.

It is an arithmetic number, because the mean of its divisors is an integer number (31415228).

Almost surely, 2^664025664 is an apocalyptic number.

664025664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

664025664 is an abundant number, since it is smaller than the sum of its proper divisors (1095227104).

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

664025664 is a wasteful number, since it uses less digits than its factorization.

664025664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4643 (or 4633 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 39.

The square root of 664025664 is about 25768.6954268158. The cubic root of 664025664 is about 872.4253739234.

The spelling of 664025664 in words is "six hundred sixty-four million, twenty-five thousand, six hundred sixty-four".