639834730 has 16 divisors (see below), whose sum is σ = 1188854784. Its totient is φ = 247677840.

The previous prime is 639834719. The next prime is 639834737. The reversal of 639834730 is 37438936.

It is not an unprimeable number, because it can be changed into a prime (639834737) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1031682 + ... + 1032301.

It is an arithmetic number, because the mean of its divisors is an integer number (74303424).

Almost surely, 2^639834730 is an apocalyptic number.

639834730 is a deficient number, since it is larger than the sum of its proper divisors (549020054).

639834730 is a wasteful number, since it uses less digits than its factorization.

639834730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2064021.

The product of its (nonzero) digits is 326592, while the sum is 43.

The square root of 639834730 is about 25294.9546352627. The cubic root of 639834730 is about 861.6996897472.

The spelling of 639834730 in words is "six hundred thirty-nine million, eight hundred thirty-four thousand, seven hundred thirty".