644364312 has 16 divisors (see below), whose sum is σ = 1610910840. Its totient is φ = 214788096.

The previous prime is 644364257. The next prime is 644364317. The reversal of 644364312 is 213463446.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644364317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13424233 + ... + 13424280.

Almost surely, 2^644364312 is an apocalyptic number.

It is an amenable number.

644364312 is an abundant number, since it is smaller than the sum of its proper divisors (966546528).

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

644364312 is a wasteful number, since it uses less digits than its factorization.

644364312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26848522 (or 26848518 counting only the distinct ones).

The product of its digits is 41472, while the sum is 33.

The square root of 644364312 is about 25384.3320179988. The cubic root of 644364312 is about 863.7283203594.

The spelling of 644364312 in words is "six hundred forty-four million, three hundred sixty-four thousand, three hundred twelve".