639505936 has 20 divisors (see below), whose sum is σ = 1240545600. Its totient is φ = 319365152.

The previous prime is 639505907. The next prime is 639505939.

It is a happy number.

639505936 is nontrivially palindromic in base 10.

It is not an unprimeable number, because it can be changed into a prime (639505939) by changing a digit.

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, 10396 + ... + 37243.

It is an arithmetic number, because the mean of its divisors is an integer number (62027280).

Almost surely, 2^639505936 is an apocalyptic number.

It is an amenable number.

639505936 is a deficient number, since it is larger than the sum of its proper divisors (601039664).

639505936 is a wasteful number, since it uses less digits than its factorization.

639505936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48486 (or 48480 counting only the distinct ones).

The product of its (nonzero) digits is 656100, while the sum is 46.

The square root of 639505936 is about 25288.4545988876. The cubic root of 639505936 is about 861.5520629623.

The spelling of 639505936 in words is "six hundred thirty-nine million, five hundred five thousand, nine hundred thirty-six".