639834438936 has 128 divisors (see below), whose sum is σ = 2011938393600. Its totient is φ = 164719994880.

The previous prime is 639834438917. The next prime is 639834438949.

639834438936 is nontrivially palindromic in base 10.

639834438936 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 (66).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1323171 + ... + 1740818.

It is an arithmetic number, because the mean of its divisors is an integer number (15718268700).

Almost surely, 2^639834438936 is an apocalyptic number.

639834438936 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

639834438936 is an abundant number, since it is smaller than the sum of its proper divisors (1372103954664).

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

639834438936 is a wasteful number, since it uses less digits than its factorization.

639834438936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3064129 (or 3064125 counting only the distinct ones).

The product of its digits is 241864704, while the sum is 66.

The spelling of 639834438936 in words is "six hundred thirty-nine billion, eight hundred thirty-four million, four hundred thirty-eight thousand, nine hundred thirty-six".