639479368 has 32 divisors (see below), whose sum is σ = 1335864960. Its totient is φ = 284486080.

The previous prime is 639479339. The next prime is 639479383. The reversal of 639479368 is 863974936.

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, 73171 + ... + 81442.

It is an arithmetic number, because the mean of its divisors is an integer number (41745780).

Almost surely, 2^639479368 is an apocalyptic number.

It is an amenable number.

639479368 is an abundant number, since it is smaller than the sum of its proper divisors (696385592).

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

639479368 is a wasteful number, since it uses less digits than its factorization.

639479368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154677 (or 154673 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 55.

The square root of 639479368 is about 25287.9292944282. The cubic root of 639479368 is about 861.5401318600.

The spelling of 639479368 in words is "six hundred thirty-nine million, four hundred seventy-nine thousand, three hundred sixty-eight".