644550132 has 12 divisors (see below), whose sum is σ = 1503950336. Its totient is φ = 214850040.

The previous prime is 644550097. The next prime is 644550149. The reversal of 644550132 is 231055446.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×644550132² = 830889745322434848, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 644550132.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26856244 + ... + 26856267.

Almost surely, 2^644550132 is an apocalyptic number.

It is an amenable number.

644550132 is an abundant number, since it is smaller than the sum of its proper divisors (859400204).

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

644550132 is a wasteful number, since it uses less digits than its factorization.

644550132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53712518 (or 53712516 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 644550132 is about 25387.9918859291. The cubic root of 644550132 is about 863.8113389086.

The spelling of 644550132 in words is "six hundred forty-four million, five hundred fifty thousand, one hundred thirty-two".