18538889475 has 24 divisors (see below), whose sum is σ = 32264175040. Its totient is φ = 9367017120.

The previous prime is 18538889471. The next prime is 18538889491. The reversal of 18538889475 is 57498883581.

It is not a de Polignac number, because 18538889475 - 2² = 18538889471 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18538889471) 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, 6503449 + ... + 6506298.

Almost surely, 2^18538889475 is an apocalyptic number.

18538889475 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18538889475 is a deficient number, since it is larger than the sum of its proper divisors (13725285565).

18538889475 is a wasteful number, since it uses less digits than its factorization.

18538889475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13009779 (or 13009774 counting only the distinct ones).

The product of its digits is 77414400, while the sum is 66.

The spelling of 18538889475 in words is "eighteen billion, five hundred thirty-eight million, eight hundred eighty-nine thousand, four hundred seventy-five".