639887630 has 8 divisors (see below), whose sum is σ = 1151797752. Its totient is φ = 255955048.

The previous prime is 639887617. The next prime is 639887653. The reversal of 639887630 is 36788936.

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, 31994372 + ... + 31994391.

It is an arithmetic number, because the mean of its divisors is an integer number (143974719).

Almost surely, 2^639887630 is an apocalyptic number.

639887630 is a deficient number, since it is larger than the sum of its proper divisors (511910122).

639887630 is a wasteful number, since it uses less digits than its factorization.

639887630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63988770.

The product of its (nonzero) digits is 1306368, while the sum is 50.

The square root of 639887630 is about 25296.0002767236. Note that the first 3 decimals coincide. The cubic root of 639887630 is about 861.7234368469.

The spelling of 639887630 in words is "six hundred thirty-nine million, eight hundred eighty-seven thousand, six hundred thirty".