18072138 has 16 divisors (see below), whose sum is σ = 41307840. Its totient is φ = 5163456.

The previous prime is 18072079. The next prime is 18072149. The reversal of 18072138 is 83127081.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 215103 + ... + 215186.

It is an arithmetic number, because the mean of its divisors is an integer number (2581740).

Almost surely, 2^18072138 is an apocalyptic number.

18072138 is an abundant number, since it is smaller than the sum of its proper divisors (23235702).

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

18072138 is a wasteful number, since it uses less digits than its factorization.

18072138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430301.

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 18072138 is about 4251.1337311357. The cubic root of 18072138 is about 262.4237746931.

The spelling of 18072138 in words is "eighteen million, seventy-two thousand, one hundred thirty-eight".