644183914 has 12 divisors (see below), whose sum is σ = 1062105282. Its totient is φ = 292810760.

The previous prime is 644183909. The next prime is 644183951. The reversal of 644183914 is 419381446.

It can be written as a sum of positive squares in only one way, i.e., 584043889 + 60140025 = 24167^2 + 7755^2 .

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 5 ways as a sum of consecutive naturals, for example, 1330717 + ... + 1331200.

Almost surely, 2^644183914 is an apocalyptic number.

644183914 is a deficient number, since it is larger than the sum of its proper divisors (417921368).

644183914 is a wasteful number, since it uses less digits than its factorization.

644183914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2661941 (or 2661930 counting only the distinct ones).

The product of its digits is 82944, while the sum is 40.

The square root of 644183914 is about 25380.7784356587. The cubic root of 644183914 is about 863.6477089197.

The spelling of 644183914 in words is "six hundred forty-four million, one hundred eighty-three thousand, nine hundred fourteen".