18117432781392 has 320 divisors, whose sum is σ = 55230170757120. Its totient is φ = 5010879283200.

The previous prime is 18117432781363. The next prime is 18117432781429. The reversal of 18117432781392 is 29318723471181.

It is a super-2 number, since 2×18117432781392² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 927614667 + ... + 927634197.

It is an arithmetic number, because the mean of its divisors is an integer number (172594283616).

Almost surely, 2^{18117432781392} is an apocalyptic number.

18117432781392 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18117432781392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27615085378560).

18117432781392 is an abundant number, since it is smaller than the sum of its proper divisors (37112737975728).

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

18117432781392 is a wasteful number, since it uses less digits than its factorization.

18117432781392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20322 (or 20316 counting only the distinct ones).

The product of its digits is 4064256, while the sum is 57.

The spelling of 18117432781392 in words is "eighteen trillion, one hundred seventeen billion, four hundred thirty-two million, seven hundred eighty-one thousand, three hundred ninety-two".