639134874 has 80 divisors (see below), whose sum is σ = 1689616896. Its totient is φ = 176709600.

The previous prime is 639134869. The next prime is 639134921. The reversal of 639134874 is 478431936.

639134874 is a `hidden beast` number, since 639 + 1 + 3 + 4 + 8 + 7 + 4 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 26064 + ... + 44244.

Almost surely, 2^639134874 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639134874, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (844808448).

639134874 is an abundant number, since it is smaller than the sum of its proper divisors (1050482022).

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

639134874 is a wasteful number, since it uses less digits than its factorization.

639134874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18233 (or 18224 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 639134874 is about 25281.1169452617. The cubic root of 639134874 is about 861.3853972782.

The spelling of 639134874 in words is "six hundred thirty-nine million, one hundred thirty-four thousand, eight hundred seventy-four".