644256495224 has 16 divisors (see below), whose sum is σ = 1224994745520. Its totient is φ = 317591229760.

The previous prime is 644256495217. The next prime is 644256495251. The reversal of 644256495224 is 422594652446.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 567126629 + ... + 567127764.

It is an arithmetic number, because the mean of its divisors is an integer number (76562171595).

Almost surely, 2^644256495224 is an apocalyptic number.

It is an amenable number.

644256495224 is a deficient number, since it is larger than the sum of its proper divisors (580738250296).

644256495224 is a wasteful number, since it uses less digits than its factorization.

644256495224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1134254470 (or 1134254466 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 53.

The spelling of 644256495224 in words is "six hundred forty-four billion, two hundred fifty-six million, four hundred ninety-five thousand, two hundred twenty-four".