639764334 has 48 divisors (see below), whose sum is σ = 1517877504. Its totient is φ = 193136400.

The previous prime is 639764311. The next prime is 639764347. The reversal of 639764334 is 433467936.

639764334 is a `hidden beast` number, since 639 + 7 + 6 + 4 + 3 + 3 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 639764334.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 47697 + ... + 59619.

It is an arithmetic number, because the mean of its divisors is an integer number (31622448).

Almost surely, 2^639764334 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639764334, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (758938752).

639764334 is an abundant number, since it is smaller than the sum of its proper divisors (878113170).

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

639764334 is a wasteful number, since it uses less digits than its factorization.

639764334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12213 (or 12210 counting only the distinct ones).

The product of its digits is 979776, while the sum is 45.

The square root of 639764334 is about 25293.5630941945. The cubic root of 639764334 is about 861.6680865673.

The spelling of 639764334 in words is "six hundred thirty-nine million, seven hundred sixty-four thousand, three hundred thirty-four".