638738880 has 336 divisors, whose sum is σ = 2284683264. Its totient is φ = 150958080.

The previous prime is 638738879. The next prime is 638738963. The reversal of 638738880 is 88837836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5029377 + ... + 5029503.

Almost surely, 2^638738880 is an apocalyptic number.

638738880 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 638738880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1142341632).

638738880 is an abundant number, since it is smaller than the sum of its proper divisors (1645944384).

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

638738880 is a wasteful number, since it uses less digits than its factorization.

638738880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 51.

The square root of 638738880 is about 25273.2839180032. The cubic root of 638738880 is about 861.2074620025.

The spelling of 638738880 in words is "six hundred thirty-eight million, seven hundred thirty-eight thousand, eight hundred eighty".