18138715056 has 360 divisors, whose sum is σ = 64325660672. Its totient is φ = 4670265600.

The previous prime is 18138715051. The next prime is 18138715079. The reversal of 18138715056 is 65051783181.

18138715056 is a `hidden beast` number, since 1 + 8 + 138 + 7 + 1 + 505 + 6 = 666.

It is a super-2 number, since 2×18138715056² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18138715051) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 15489351 + ... + 15490521.

Almost surely, 2^18138715056 is an apocalyptic number.

18138715056 is a gapful number since it is divisible by the number (16) 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 18138715056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32162830336).

18138715056 is an abundant number, since it is smaller than the sum of its proper divisors (46186945616).

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

18138715056 is a wasteful number, since it uses less digits than its factorization.

18138715056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1341 (or 1321 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The spelling of 18138715056 in words is "eighteen billion, one hundred thirty-eight million, seven hundred fifteen thousand, fifty-six".