639426132 has 72 divisors (see below), whose sum is σ = 1659359520. Its totient is φ = 207529920.

The previous prime is 639426103. The next prime is 639426149. The reversal of 639426132 is 231624936.

639426132 is a `hidden beast` number, since 6 + 39 + 4 + 2 + 613 + 2 = 666.

639426132 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 264007 + ... + 266417.

It is an arithmetic number, because the mean of its divisors is an integer number (23046660).

Almost surely, 2^639426132 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 639426132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (829679760).

639426132 is an abundant number, since it is smaller than the sum of its proper divisors (1019933388).

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

639426132 is a wasteful number, since it uses less digits than its factorization.

639426132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2613 (or 2608 counting only the distinct ones).

The product of its digits is 46656, while the sum is 36.

The square root of 639426132 is about 25286.8766754615. The cubic root of 639426132 is about 861.5162237531.

The spelling of 639426132 in words is "six hundred thirty-nine million, four hundred twenty-six thousand, one hundred thirty-two".