18638264403215 has 16 divisors (see below), whose sum is σ = 22673403292608. Its totient is φ = 14705640734976.

The previous prime is 18638264403203. The next prime is 18638264403221. The reversal of 18638264403215 is 51230446283681.

It is a cyclic number.

It is not a de Polignac number, because 18638264403215 - 2⁸ = 18638264402959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6329294 + ... + 8794116.

It is an arithmetic number, because the mean of its divisors is an integer number (1417087705788).

Almost surely, 2^{18638264403215} is an apocalyptic number.

18638264403215 is a deficient number, since it is larger than the sum of its proper divisors (4035138889393).

18638264403215 is a wasteful number, since it uses less digits than its factorization.

18638264403215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2485618.

The product of its (nonzero) digits is 6635520, while the sum is 53.

The spelling of 18638264403215 in words is "eighteen trillion, six hundred thirty-eight billion, two hundred sixty-four million, four hundred three thousand, two hundred fifteen".