638818870812 has 48 divisors (see below), whose sum is σ = 1581143961600. Its totient is φ = 200047341312.

The previous prime is 638818870793. The next prime is 638818870841. The reversal of 638818870812 is 218078818836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2750812 + ... + 2973987.

It is an arithmetic number, because the mean of its divisors is an integer number (32940499200).

Almost surely, 2^638818870812 is an apocalyptic number.

It is an amenable number.

638818870812 is an abundant number, since it is smaller than the sum of its proper divisors (942325090788).

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

638818870812 is a wasteful number, since it uses less digits than its factorization.

638818870812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5725370 (or 5725368 counting only the distinct ones).

The product of its (nonzero) digits is 8257536, while the sum is 60.

The spelling of 638818870812 in words is "six hundred thirty-eight billion, eight hundred eighteen million, eight hundred seventy thousand, eight hundred twelve".