18137128728 has 96 divisors (see below), whose sum is σ = 47813245200. Its totient is φ = 5726482944.

The previous prime is 18137128697. The next prime is 18137128729. The reversal of 18137128728 is 82782173181.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18137128729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1950426 + ... + 1959702.

Almost surely, 2^18137128728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18137128728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23906622600).

18137128728 is an abundant number, since it is smaller than the sum of its proper divisors (29676116472).

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

18137128728 is a wasteful number, since it uses less digits than its factorization.

18137128728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9421 (or 9364 counting only the distinct ones).

The product of its digits is 301056, while the sum is 48.

The spelling of 18137128728 in words is "eighteen billion, one hundred thirty-seven million, one hundred twenty-eight thousand, seven hundred twenty-eight".