18156 has 24 divisors (see below), whose sum is σ = 45360. Its totient is φ = 5632.

The previous prime is 18149. The next prime is 18169. The reversal of 18156 is 65181.

18156 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 14.

It is a nialpdrome in base 12.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18156.

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, 160 + ... + 248.

It is an arithmetic number, because the mean of its divisors is an integer number (1890).

2¹⁸¹⁵⁶ 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 18156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22680).

18156 is an abundant number, since it is smaller than the sum of its proper divisors (27204).

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

18156 is a wasteful number, since it uses less digits than its factorization.

18156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 111 counting only the distinct ones).

The product of its digits is 240, while the sum is 21.

The square root of 18156 is about 134.7442021016. The cubic root of 18156 is about 26.2829065774.

The spelling of 18156 in words is "eighteen thousand, one hundred fifty-six".