644514757752 has 32 divisors (see below), whose sum is σ = 1611311058000. Its totient is φ = 214835030784.

The previous prime is 644514757727. The next prime is 644514757879. The reversal of 644514757752 is 257757415446.

It is a junction number, because it is equal to n+sod(n) for n = 644514757692 and 644514757701.

It is a congruent 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, 1865188 + ... + 2183564.

Almost surely, 2^644514757752 is an apocalyptic number.

It is an amenable number.

644514757752 is an abundant number, since it is smaller than the sum of its proper divisors (966796300248).

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

644514757752 is a wasteful number, since it uses less digits than its factorization.

644514757752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402735 (or 402731 counting only the distinct ones).

The product of its digits is 32928000, while the sum is 57.

The spelling of 644514757752 in words is "six hundred forty-four billion, five hundred fourteen million, seven hundred fifty-seven thousand, seven hundred fifty-two".