639350136 has 96 divisors (see below), whose sum is σ = 1815708960. Its totient is φ = 202853376.

The previous prime is 639350123. The next prime is 639350147. The reversal of 639350136 is 631053936.

639350136 is a `hidden beast` number, since 63 + 93 + 501 + 3 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 639350136.

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, 385020 + ... + 386676.

It is an arithmetic number, because the mean of its divisors is an integer number (18913635).

Almost surely, 2^639350136 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 639350136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (907854480).

639350136 is an abundant number, since it is smaller than the sum of its proper divisors (1176358824).

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

639350136 is a wasteful number, since it uses less digits than its factorization.

639350136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1925 (or 1918 counting only the distinct ones).

The product of its (nonzero) digits is 43740, while the sum is 36.

The square root of 639350136 is about 25285.3739541261. The cubic root of 639350136 is about 861.4820919081.

The spelling of 639350136 in words is "six hundred thirty-nine million, three hundred fifty thousand, one hundred thirty-six".