It is a tau number, because it is divible by the number of its divisors (48).
It is a nialpdrome in base 12.
It is a congruent number.
It is an unprimeable number.
218816 is an apocalyptic number.
18816 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 18816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29070).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
18816 is an equidigital number, since it uses as much as digits as its factorization.
18816 is an evil number, because the sum of its binary digits is even.
The square root of 18816 is about 137.1714255959. The cubic root of 18816 is about 26.5975990446.
Multiplying 18816 by its sum of digits (24), we get a square (451584 = 6722).
18816 divided by its sum of digits (24) gives a square (784 = 282).
Multiplying 18816 by its product of digits (384), we get a square (7225344 = 26882).
18816 divided by its product of digits (384) gives a square (49 = 72).
The spelling of 18816 in words is "eighteen thousand, eight hundred sixteen".