638884454432 has 96 divisors (see below), whose sum is σ = 1525102992000. Its totient is φ = 257184092160.

The previous prime is 638884454413. The next prime is 638884454459. The reversal of 638884454432 is 234454488836.

It is a super-2 number, since 2×638884454432² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1732082 + ... + 2068302.

It is an arithmetic number, because the mean of its divisors is an integer number (15886489500).

Almost surely, 2^638884454432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638884454432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (762551496000).

638884454432 is an abundant number, since it is smaller than the sum of its proper divisors (886218537568).

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

638884454432 is a wasteful number, since it uses less digits than its factorization.

638884454432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336754 (or 336746 counting only the distinct ones).

The product of its digits is 70778880, while the sum is 59.

The spelling of 638884454432 in words is "six hundred thirty-eight billion, eight hundred eighty-four million, four hundred fifty-four thousand, four hundred thirty-two".