638125133769 has 24 divisors (see below), whose sum is σ = 951453514440. Its totient is φ = 411817851648.

The previous prime is 638125133749. The next prime is 638125133881. The reversal of 638125133769 is 967331521836.

638125133769 is a `hidden beast` number, since 6 + 38 + 1 + 2 + 513 + 37 + 69 = 666.

638125133769 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 372054861369 + 266070272400 = 609963^2 + 515820^2 .

It is not a de Polignac number, because 638125133769 - 2²⁴ = 638108356553 is a prime.

It is a super-2 number, since 2×638125133769² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638125133729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4798084 + ... + 4929285.

It is an arithmetic number, because the mean of its divisors is an integer number (39643896435).

Almost surely, 2^638125133769 is an apocalyptic number.

It is an amenable number.

638125133769 is a deficient number, since it is larger than the sum of its proper divisors (313328380671).

638125133769 is a wasteful number, since it uses less digits than its factorization.

638125133769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9727609 (or 9727606 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 54.

The spelling of 638125133769 in words is "six hundred thirty-eight billion, one hundred twenty-five million, one hundred thirty-three thousand, seven hundred sixty-nine".