639437632 has 28 divisors (see below), whose sum is σ = 1295887680. Its totient is φ = 312914816.

The previous prime is 639437611. The next prime is 639437641. The reversal of 639437632 is 236734936.

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 3 ways as a sum of consecutive naturals, for example, 103282 + ... + 109297.

Almost surely, 2^639437632 is an apocalyptic number.

It is an amenable number.

639437632 is an abundant number, since it is smaller than the sum of its proper divisors (656450048).

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

639437632 is a wasteful number, since it uses less digits than its factorization.

639437632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212638 (or 212628 counting only the distinct ones).

The product of its digits is 489888, while the sum is 43.

The square root of 639437632 is about 25287.1040651159. The cubic root of 639437632 is about 861.5213884764.

The spelling of 639437632 in words is "six hundred thirty-nine million, four hundred thirty-seven thousand, six hundred thirty-two".