16644639732 has 48 divisors (see below), whose sum is σ = 44816658432. Its totient is φ = 4709437920.

The previous prime is 16644639721. The next prime is 16644639751. The reversal of 16644639732 is 23793644661.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 953244 + ... + 970547.

It is an arithmetic number, because the mean of its divisors is an integer number (933680384).

Almost surely, 2^16644639732 is an apocalyptic number.

16644639732 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16644639732 is an abundant number, since it is smaller than the sum of its proper divisors (28172018700).

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

16644639732 is a wasteful number, since it uses less digits than its factorization.

16644639732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1923908 (or 1923906 counting only the distinct ones).

The product of its digits is 3919104, while the sum is 51.

The spelling of 16644639732 in words is "sixteen billion, six hundred forty-four million, six hundred thirty-nine thousand, seven hundred thirty-two".