638944080 has 160 divisors (see below), whose sum is σ = 2024870400. Its totient is φ = 166642176.

The previous prime is 638944003. The next prime is 638944091. The reversal of 638944080 is 80449836.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3569431 + ... + 3569609.

It is an arithmetic number, because the mean of its divisors is an integer number (12655440).

Almost surely, 2^638944080 is an apocalyptic number.

638944080 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638944080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012435200).

638944080 is an abundant number, since it is smaller than the sum of its proper divisors (1385926320).

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

638944080 is a wasteful number, since it uses less digits than its factorization.

638944080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441 (or 435 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 638944080 is about 25277.3432148238. The cubic root of 638944080 is about 861.2996754019.

The spelling of 638944080 in words is "six hundred thirty-eight million, nine hundred forty-four thousand, eighty".