639433642494 has 32 divisors (see below), whose sum is σ = 1286359038720. Its totient is φ = 211896565632.

The previous prime is 639433642453. The next prime is 639433642553. The reversal of 639433642494 is 494246334936.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3995199 + ... + 4152165.

It is an arithmetic number, because the mean of its divisors is an integer number (40198719960).

Almost surely, 2^639433642494 is an apocalyptic number.

639433642494 is an abundant number, since it is smaller than the sum of its proper divisors (646925396226).

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

639433642494 is a wasteful number, since it uses less digits than its factorization.

639433642494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160944.

The product of its digits is 40310784, while the sum is 57.

The spelling of 639433642494 in words is "six hundred thirty-nine billion, four hundred thirty-three million, six hundred forty-two thousand, four hundred ninety-four".