639031671663 has 96 divisors (see below), whose sum is σ = 1142606787840. Its totient is φ = 313265111040.

The previous prime is 639031671659. The next prime is 639031671713. The reversal of 639031671663 is 366176130936.

It is not a de Polignac number, because 639031671663 - 2² = 639031671659 is a prime.

It is a super-2 number, since 2×639031671663² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639031675663) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7855345 + ... + 7936277.

It is an arithmetic number, because the mean of its divisors is an integer number (11902154040).

Almost surely, 2^639031671663 is an apocalyptic number.

639031671663 is a deficient number, since it is larger than the sum of its proper divisors (503575116177).

639031671663 is a wasteful number, since it uses less digits than its factorization.

639031671663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81237 (or 81230 counting only the distinct ones).

The product of its (nonzero) digits is 2204496, while the sum is 51.

The spelling of 639031671663 in words is "six hundred thirty-nine billion, thirty-one million, six hundred seventy-one thousand, six hundred sixty-three".