Subtracting from 918 its sum of digits (18), we obtain a square (900 = 302).
Adding to 918 its product of digits (72), we get a triangular number (990 = T44).
Subtracting from 918 its reverse (819), we obtain a palindrome (99).
918 is nontrivially palindromic in base 12.
918 is an esthetic number in base 11, because in such base its adjacent digits differ by 1.
918 is an undulating number in base 12.
It is a plaindrome in base 13.
It is a nialpdrome in base 11.
It is a self number, because there is not a number n which added to its sum of digits gives 918.
It is a congruent number.
It is a practical number, because each smaller number is the sum of distinct divisors of 918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1080).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
918 is a wasteful number, since it uses less digits than its factorization.
918 is an evil number, because the sum of its binary digits is even.
The square root of 918 is about 30.2985148151. The cubic root of 918 is about 9.7188354038.