638226622836 has 192 divisors, whose sum is σ = 1854122054400. Its totient is φ = 188173670400.

The previous prime is 638226622829. The next prime is 638226622921.

638226622836 is a `hidden beast` number, since 6 + 3 + 8 + 2 + 2 + 6 + 622 + 8 + 3 + 6 = 666.

638226622836 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 18150520 + ... + 18185648.

It is an arithmetic number, because the mean of its divisors is an integer number (9656885700).

Almost surely, 2^638226622836 is an apocalyptic number.

638226622836 is a gapful number since it is divisible by the number (66) 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 638226622836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (927061027200).

638226622836 is an abundant number, since it is smaller than the sum of its proper divisors (1215895431564).

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

638226622836 is a wasteful number, since it uses less digits than its factorization.

638226622836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35567 (or 35559 counting only the distinct ones).

The product of its digits is 11943936, while the sum is 54.

The spelling of 638226622836 in words is "six hundred thirty-eight billion, two hundred twenty-six million, six hundred twenty-two thousand, eight hundred thirty-six".