638912232 has 256 divisors, whose sum is σ = 2149171200. Its totient is φ = 172005120.

The previous prime is 638912203. The next prime is 638912237. The reversal of 638912232 is 232219836.

638912232 is a `hidden beast` number, since 638 + 9 + 12 + 2 + 3 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (638912237) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2015338 + ... + 2015654.

It is an arithmetic number, because the mean of its divisors is an integer number (8395200).

Almost surely, 2^638912232 is an apocalyptic number.

638912232 is a gapful number since it is divisible by the number (62) 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 638912232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1074585600).

638912232 is an abundant number, since it is smaller than the sum of its proper divisors (1510258968).

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

638912232 is a wasteful number, since it uses less digits than its factorization.

638912232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 403 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 638912232 is about 25276.7132357037. The cubic root of 638912232 is about 861.2853647454.

The spelling of 638912232 in words is "six hundred thirty-eight million, nine hundred twelve thousand, two hundred thirty-two".