639949746726 has 48 divisors (see below), whose sum is σ = 1416239068608. Its totient is φ = 208751385600.

The previous prime is 639949746701. The next prime is 639949746749. The reversal of 639949746726 is 627647949936.

639949746726 is a `hidden beast` number, since 6 + 3 + 99 + 497 + 46 + 7 + 2 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7266516 + ... + 7354056.

It is an arithmetic number, because the mean of its divisors is an integer number (29504980596).

Almost surely, 2^639949746726 is an apocalyptic number.

639949746726 is an abundant number, since it is smaller than the sum of its proper divisors (776289321882).

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

639949746726 is a wasteful number, since it uses less digits than its factorization.

639949746726 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96237 (or 96234 counting only the distinct ones).

The product of its digits is 740710656, while the sum is 72.

The spelling of 639949746726 in words is "six hundred thirty-nine billion, nine hundred forty-nine million, seven hundred forty-six thousand, seven hundred twenty-six".