It is a happy number.
989 is nontrivially palindromic in base 10.
989 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.
It is a cyclic number.
It is an alternating number because its digits alternate between odd and even.
It is a Duffinian number.
989 is an undulating number in base 10.
It is a Curzon number.
It is a plaindrome in base 15 and base 16.
It is a congruent number.
It is an amenable number.
989 is a wasteful number, since it uses less digits than its factorization.
989 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 66.
The square root of 989 is about 31.4483703870. The cubic root of 989 is about 9.9631980612.