Adding to 18000 its reverse (81), we get a palindrome (18081).
It is a tau number, because it is divible by the number of its divisors (60).
It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.
It is a nialpdrome in base 12 and base 15.
It is a zygodrome in base 15.
It is a congruent number.
It is an unprimeable number.
18000 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
218000 is an apocalyptic number.
18000 is a gapful number since it is divisible by the number (10) 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 18000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31434).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
18000 is a wasteful number, since it uses less digits than its factorization.
18000 is an odious number, because the sum of its binary digits is odd.
The square root of 18000 is about 134.1640786500. The cubic root of 18000 is about 26.2074139421.
The spelling of 18000 in words is "eighteen thousand".