18135398938923 has 144 divisors (see below), whose sum is σ = 31371030608736. Its totient is φ = 10063004958720.

The previous prime is 18135398938919. The next prime is 18135398938933. The reversal of 18135398938923 is 32983989353181.

18135398938923 is a `hidden beast` number, since 1 + 8 + 1 + 3 + 539 + 8 + 9 + 3 + 89 + 2 + 3 = 666.

It is not a de Polignac number, because 18135398938923 - 2² = 18135398938919 is a prime.

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (18135398938913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 602670108 + ... + 602700198.

Almost surely, 2^{18135398938923} is an apocalyptic number.

18135398938923 is a deficient number, since it is larger than the sum of its proper divisors (13235631669813).

18135398938923 is a wasteful number, since it uses less digits than its factorization.

18135398938923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30474 (or 30464 counting only the distinct ones).

The product of its digits is 302330880, while the sum is 72.

The spelling of 18135398938923 in words is "eighteen trillion, one hundred thirty-five billion, three hundred ninety-eight million, nine hundred thirty-eight thousand, nine hundred twenty-three".