644183364 has 24 divisors (see below), whose sum is σ = 1639739808. Its totient is φ = 195207040.

The previous prime is 644183347. The next prime is 644183377. The reversal of 644183364 is 463381446.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2439957 + ... + 2440220.

It is an arithmetic number, because the mean of its divisors is an integer number (68322492).

Almost surely, 2^644183364 is an apocalyptic number.

It is an amenable number.

644183364 is an abundant number, since it is smaller than the sum of its proper divisors (995556444).

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

644183364 is a wasteful number, since it uses less digits than its factorization.

644183364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4880195 (or 4880193 counting only the distinct ones).

The product of its digits is 165888, while the sum is 39.

The square root of 644183364 is about 25380.7676006854. The cubic root of 644183364 is about 863.6474631274.

The spelling of 644183364 in words is "six hundred forty-four million, one hundred eighty-three thousand, three hundred sixty-four".