644313650 has 24 divisors (see below), whose sum is σ = 1207058160. Its totient is φ = 255868560.

The previous prime is 644313629. The next prime is 644313667. The reversal of 644313650 is 56313446.

644313650 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39404 + ... + 53303.

It is an arithmetic number, because the mean of its divisors is an integer number (50294090).

Almost surely, 2^644313650 is an apocalyptic number.

644313650 is a deficient number, since it is larger than the sum of its proper divisors (562744510).

644313650 is a wasteful number, since it uses less digits than its factorization.

644313650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92858 (or 92853 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 32.

The square root of 644313650 is about 25383.3340993653. The cubic root of 644313650 is about 863.7056833975.

The spelling of 644313650 in words is "six hundred forty-four million, three hundred thirteen thousand, six hundred fifty".