644702716 has 24 divisors (see below), whose sum is σ = 1290060800. Its totient is φ = 276160752.

The previous prime is 644702701. The next prime is 644702761. The reversal of 644702716 is 617207446.

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 7 ways as a sum of consecutive naturals, for example, 65485 + ... + 74683.

Almost surely, 2^644702716 is an apocalyptic number.

It is an amenable number.

644702716 is an abundant number, since it is smaller than the sum of its proper divisors (645358084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644702716 is a wasteful number, since it uses less digits than its factorization.

644702716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11713 (or 11711 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 37.

The square root of 644702716 is about 25390.9967508170. The cubic root of 644702716 is about 863.8794967257.

The spelling of 644702716 in words is "six hundred forty-four million, seven hundred two thousand, seven hundred sixteen".