638638274670 has 96 divisors (see below), whose sum is σ = 1730272156704. Its totient is φ = 150637006080.

The previous prime is 638638274629. The next prime is 638638274671. The reversal of 638638274670 is 76472836836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638638274671) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2243169 + ... + 2511788.

It is an arithmetic number, because the mean of its divisors is an integer number (18023668299).

Almost surely, 2^638638274670 is an apocalyptic number.

638638274670 is an abundant number, since it is smaller than the sum of its proper divisors (1091633882034).

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

638638274670 is a wasteful number, since it uses less digits than its factorization.

638638274670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4755026 (or 4755015 counting only the distinct ones).

The product of its (nonzero) digits is 48771072, while the sum is 60.

The spelling of 638638274670 in words is "six hundred thirty-eight billion, six hundred thirty-eight million, two hundred seventy-four thousand, six hundred seventy".