• 2162 = 46656 is the smallest square that contains exactly three digits '6'.
Adding to 216 its reverse (612), we get a palindrome (828).
The cubic root of 216 is 6.
It is a Jordan-Polya number, since it can be written as (3!)3.
216 is nontrivially palindromic in base 5.
216 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.
It is an alternating number because its digits alternate between even and odd.
216 is strictly pandigital in base 4.
It is a plaindrome in base 13 and base 14.
It is a nialpdrome in base 3, base 6, base 8, base 15 and base 16.
It is a zygodrome in base 3.
It is a congruent number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216.
216 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
216 is a Friedman number, since it can be written as 6^(2+1), using all its digits and the basic arithmetic operations.
It is an amenable number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
216 is a wasteful number, since it uses less digits than its factorization.
216 is an evil number, because the sum of its binary digits is even.
The square root of 216 is about 14.6969384567.
The spelling of 216 in words is "two hundred sixteen", and thus it is an aban number.