639801683 has 12 divisors (see below), whose sum is σ = 664161888. Its totient is φ = 616308000.

The previous prime is 639801667. The next prime is 639801689. The reversal of 639801683 is 386108936.

It is not a de Polignac number, because 639801683 - 2⁴ = 639801667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639801689) 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 11 ways as a sum of consecutive naturals, for example, 631085 + ... + 632097.

It is an arithmetic number, because the mean of its divisors is an integer number (55346824).

Almost surely, 2^639801683 is an apocalyptic number.

639801683 is a deficient number, since it is larger than the sum of its proper divisors (24360205).

639801683 is a wasteful number, since it uses less digits than its factorization.

639801683 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1822 (or 1793 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 639801683 is about 25294.3013937922. The cubic root of 639801683 is about 861.6848541036.

The spelling of 639801683 in words is "six hundred thirty-nine million, eight hundred one thousand, six hundred eighty-three".