638252076444 has 12 divisors (see below), whose sum is σ = 1489254845064. Its totient is φ = 212750692144.

The previous prime is 638252076443. The next prime is 638252076503. The reversal of 638252076444 is 444670252836.

638252076444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638252076443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26593836507 + ... + 26593836530.

It is an arithmetic number, because the mean of its divisors is an integer number (124104570422).

Almost surely, 2^638252076444 is an apocalyptic number.

It is an amenable number.

638252076444 is an abundant number, since it is smaller than the sum of its proper divisors (851002768620).

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

638252076444 is a wasteful number, since it uses less digits than its factorization.

638252076444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53187673044 (or 53187673042 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 51.

The spelling of 638252076444 in words is "six hundred thirty-eight billion, two hundred fifty-two million, seventy-six thousand, four hundred forty-four".