Adding to 16815 its sum of digits (21), we get a triangular number (16836 = T183).
16815 is digitally balanced in base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.
It is a congruent number.
16815 is a Friedman number, since it can be written as 8+(6+1)^(5*1), using all its digits and the basic arithmetic operations.
216815 is an apocalyptic number.
16815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.
16815 is a wasteful number, since it uses less digits than its factorization.
16815 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 86.
The square root of 16815 is about 129.6726648141. The cubic root of 16815 is about 25.6192035273.
The spelling of 16815 in words is "sixteen thousand, eight hundred fifteen".