18218365640408 has 16 divisors (see below), whose sum is σ = 34738409061000. Its totient is φ = 8954789890816.

The previous prime is 18218365640399. The next prime is 18218365640429. The reversal of 18218365640408 is 80404656381281.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19299115673 + ... + 19299116616.

Almost surely, 2^{18218365640408} is an apocalyptic number.

It is an amenable number.

18218365640408 is a deficient number, since it is larger than the sum of its proper divisors (16520043420592).

18218365640408 is a wasteful number, since it uses less digits than its factorization.

18218365640408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38598232354 (or 38598232350 counting only the distinct ones).

The product of its (nonzero) digits is 8847360, while the sum is 56.

The spelling of 18218365640408 in words is "eighteen trillion, two hundred eighteen billion, three hundred sixty-five million, six hundred forty thousand, four hundred eight".