639082920 has 64 divisors (see below), whose sum is σ = 2191144320. Its totient is φ = 146075904.

The previous prime is 639082901. The next prime is 639082963. The reversal of 639082920 is 29280936.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 379567 + ... + 381246.

It is an arithmetic number, because the mean of its divisors is an integer number (34236630).

Almost surely, 2^639082920 is an apocalyptic number.

639082920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

639082920 is an abundant number, since it is smaller than the sum of its proper divisors (1552061400).

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

639082920 is a wasteful number, since it uses less digits than its factorization.

639082920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760834 (or 760830 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 39.

The square root of 639082920 is about 25280.0893985761. The cubic root of 639082920 is about 861.3620565451.

The spelling of 639082920 in words is "six hundred thirty-nine million, eighty-two thousand, nine hundred twenty".