18438912 has 108 divisors (see below), whose sum is σ = 54525744. Its totient is φ = 5990400.

The previous prime is 18438907. The next prime is 18438919. The reversal of 18438912 is 21983481.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (18438919) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 122037 + ... + 122187.

It is an arithmetic number, because the mean of its divisors is an integer number (504868).

Almost surely, 2^18438912 is an apocalyptic number.

18438912 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 18438912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27262872).

18438912 is an abundant number, since it is smaller than the sum of its proper divisors (36086832).

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

18438912 is a wasteful number, since it uses less digits than its factorization.

18438912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 209 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 18438912 is about 4294.0554258183. The cubic root of 18438912 is about 264.1871950575.

The spelling of 18438912 in words is "eighteen million, four hundred thirty-eight thousand, nine hundred twelve".