639748632 has 32 divisors (see below), whose sum is σ = 1604001600. Its totient is φ = 212632224.

The previous prime is 639748609. The next prime is 639748661. The reversal of 639748632 is 236847936.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30082 + ... + 46737.

It is an arithmetic number, because the mean of its divisors is an integer number (50125050).

Almost surely, 2^639748632 is an apocalyptic number.

It is an amenable number.

639748632 is an abundant number, since it is smaller than the sum of its proper divisors (964252968).

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

639748632 is a wasteful number, since it uses less digits than its factorization.

639748632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77175 (or 77171 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 48.

The square root of 639748632 is about 25293.2526971127. The cubic root of 639748632 is about 861.6610370845.

The spelling of 639748632 in words is "six hundred thirty-nine million, seven hundred forty-eight thousand, six hundred thirty-two".