644311316 has 24 divisors (see below), whose sum is σ = 1269730560. Its totient is φ = 283420800.

The previous prime is 644311309. The next prime is 644311319. The reversal of 644311316 is 613113446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644311319) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 234821 + ... + 237548.

It is an arithmetic number, because the mean of its divisors is an integer number (52905440).

Almost surely, 2^644311316 is an apocalyptic number.

It is an amenable number.

644311316 is a deficient number, since it is larger than the sum of its proper divisors (625419244).

644311316 is a wasteful number, since it uses less digits than its factorization.

644311316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472415 (or 472413 counting only the distinct ones).

The product of its digits is 5184, while the sum is 29.

The square root of 644311316 is about 25383.2881242758. The cubic root of 644311316 is about 863.7046404834.

The spelling of 644311316 in words is "six hundred forty-four million, three hundred eleven thousand, three hundred sixteen".