18215645939975 has 12 divisors (see below), whose sum is σ = 24640801053720. Its totient is φ = 13247742501600.

The previous prime is 18215645939957. The next prime is 18215645940007. The reversal of 18215645939975 is 57993954651281.

It is not a de Polignac number, because 18215645939975 - 2²⁰ = 18215644891399 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33119355980 + ... + 33119356529.

It is an arithmetic number, because the mean of its divisors is an integer number (2053400087810).

Almost surely, 2^{18215645939975} is an apocalyptic number.

18215645939975 is a deficient number, since it is larger than the sum of its proper divisors (6425155113745).

18215645939975 is a wasteful number, since it uses less digits than its factorization.

18215645939975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66238712530 (or 66238712525 counting only the distinct ones).

The product of its digits is 734832000, while the sum is 74.

The spelling of 18215645939975 in words is "eighteen trillion, two hundred fifteen billion, six hundred forty-five million, nine hundred thirty-nine thousand, nine hundred seventy-five".