639891230 has 32 divisors (see below), whose sum is σ = 1257596928. Its totient is φ = 232487200.

The previous prime is 639891179. The next prime is 639891247. The reversal of 639891230 is 32198936.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 198935 + ... + 202125.

It is an arithmetic number, because the mean of its divisors is an integer number (39299904).

Almost surely, 2^639891230 is an apocalyptic number.

639891230 is a deficient number, since it is larger than the sum of its proper divisors (617705698).

639891230 is a wasteful number, since it uses less digits than its factorization.

639891230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5032.

The product of its (nonzero) digits is 69984, while the sum is 41.

The square root of 639891230 is about 25296.0714341180. The cubic root of 639891230 is about 861.7250528590.

The spelling of 639891230 in words is "six hundred thirty-nine million, eight hundred ninety-one thousand, two hundred thirty".