638188763125 has 20 divisors (see below), whose sum is σ = 805376606364. Its totient is φ = 505496000000.

The previous prime is 638188763119. The next prime is 638188763153. The reversal of 638188763125 is 521367881836.

It is a happy number.

It can be written as a sum of positive squares in 10 ways, for example, as 423258239889 + 214930523236 = 650583^2 + 463606^2 .

It is not a de Polignac number, because 638188763125 - 2²⁷ = 638054545397 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638188763125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4991836 + ... + 5118085.

Almost surely, 2^638188763125 is an apocalyptic number.

It is an amenable number.

638188763125 is a deficient number, since it is larger than the sum of its proper divisors (167187843239).

638188763125 is a wasteful number, since it uses less digits than its factorization.

638188763125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10110042 (or 10110027 counting only the distinct ones).

The product of its digits is 11612160, while the sum is 58.

The spelling of 638188763125 in words is "six hundred thirty-eight billion, one hundred eighty-eight million, seven hundred sixty-three thousand, one hundred twenty-five".