639847016556 has 24 divisors (see below), whose sum is σ = 1628701497024. Its totient is φ = 193893035280.

The previous prime is 639847016531. The next prime is 639847016579. The reversal of 639847016556 is 655610748936.

It is a super-2 number, since 2×639847016556² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 639847016556.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2423662810 + ... + 2423663073.

It is an arithmetic number, because the mean of its divisors is an integer number (67862562376).

Almost surely, 2^639847016556 is an apocalyptic number.

639847016556 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

639847016556 is an abundant number, since it is smaller than the sum of its proper divisors (988854480468).

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

639847016556 is a wasteful number, since it uses less digits than its factorization.

639847016556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4847325901 (or 4847325899 counting only the distinct ones).

The product of its (nonzero) digits is 32659200, while the sum is 60.

The spelling of 639847016556 in words is "six hundred thirty-nine billion, eight hundred forty-seven million, sixteen thousand, five hundred fifty-six".