639971814144 has 576 divisors, whose sum is σ = 1982635522560. Its totient is φ = 181520302080.

The previous prime is 639971814091. The next prime is 639971814173. The reversal of 639971814144 is 441418179936.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2379077242 + ... + 2379077510.

It is an arithmetic number, because the mean of its divisors is an integer number (3442075560).

Almost surely, 2^639971814144 is an apocalyptic number.

639971814144 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639971814144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (991317761280).

639971814144 is an abundant number, since it is smaller than the sum of its proper divisors (1342663708416).

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

639971814144 is a wasteful number, since it uses less digits than its factorization.

639971814144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 556 (or 542 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 57.

The spelling of 639971814144 in words is "six hundred thirty-nine billion, nine hundred seventy-one million, eight hundred fourteen thousand, one hundred forty-four".