639216790 has 8 divisors (see below), whose sum is σ = 1150590240. Its totient is φ = 255686712.

The previous prime is 639216757. The next prime is 639216827. The reversal of 639216790 is 97612936.

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, 31960830 + ... + 31960849.

It is an arithmetic number, because the mean of its divisors is an integer number (143823780).

Almost surely, 2^639216790 is an apocalyptic number.

639216790 is a deficient number, since it is larger than the sum of its proper divisors (511373450).

639216790 is a wasteful number, since it uses less digits than its factorization.

639216790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63921686.

The product of its (nonzero) digits is 122472, while the sum is 43.

The square root of 639216790 is about 25282.7369958239. The cubic root of 639216790 is about 861.4221961005.

The spelling of 639216790 in words is "six hundred thirty-nine million, two hundred sixteen thousand, seven hundred ninety".