13538187657 has 12 divisors (see below), whose sum is σ = 19558003140. Its totient is φ = 9024146208.

The previous prime is 13538187647. The next prime is 13538187703. The reversal of 13538187657 is 75678183531.

13538187657 is a `hidden beast` number, since 135 + 381 + 87 + 6 + 57 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 4446755856 + 9091431801 = 66684^2 + 95349^2 .

It is not a de Polignac number, because 13538187657 - 2⁷ = 13538187529 is a prime.

It is a super-2 number, since 2×13538187657² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13538187647) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41818 + ... + 169779.

It is an arithmetic number, because the mean of its divisors is an integer number (1629833595).

Almost surely, 2^13538187657 is an apocalyptic number.

It is an amenable number.

13538187657 is a deficient number, since it is larger than the sum of its proper divisors (6019815483).

13538187657 is a wasteful number, since it uses less digits than its factorization.

13538187657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218712 (or 218709 counting only the distinct ones).

The product of its digits is 4233600, while the sum is 54.

The spelling of 13538187657 in words is "thirteen billion, five hundred thirty-eight million, one hundred eighty-seven thousand, six hundred fifty-seven".