18387768921368 has 72 divisors (see below), whose sum is σ = 44083427818500. Its totient is φ = 7164065795040.

The previous prime is 18387768921341. The next prime is 18387768921377. The reversal of 18387768921368 is 86312986778381.

It is a super-2 number, since 2×18387768921368² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (77).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 193785518 + ... + 193880381.

Almost surely, 2^{18387768921368} is an apocalyptic number.

It is an amenable number.

18387768921368 is an abundant number, since it is smaller than the sum of its proper divisors (25695658897132).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18387768921368 is a wasteful number, since it uses less digits than its factorization.

18387768921368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387665941 (or 387665919 counting only the distinct ones).

The product of its digits is 1170505728, while the sum is 77.

The spelling of 18387768921368 in words is "eighteen trillion, three hundred eighty-seven billion, seven hundred sixty-eight million, nine hundred twenty-one thousand, three hundred sixty-eight".