639747934 has 8 divisors (see below), whose sum is σ = 1096710768. Its totient is φ = 274177680.

The previous prime is 639747919. The next prime is 639747943. The reversal of 639747934 is 439747936.

639747934 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22848127 + ... + 22848154.

It is an arithmetic number, because the mean of its divisors is an integer number (137088846).

Almost surely, 2^639747934 is an apocalyptic number.

639747934 is a deficient number, since it is larger than the sum of its proper divisors (456962834).

639747934 is a wasteful number, since it uses less digits than its factorization.

639747934 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45696290.

The product of its digits is 3429216, while the sum is 52.

The square root of 639747934 is about 25293.2388989627. The cubic root of 639747934 is about 861.6607237116.

The spelling of 639747934 in words is "six hundred thirty-nine million, seven hundred forty-seven thousand, nine hundred thirty-four".