549 is nontrivially palindromic in base 13.
It is an alternating number because its digits alternate between odd and even.
It is a Duffinian number.
549 is a nontrivial repdigit in base 13.
It is a plaindrome in base 11, base 12, base 13, base 15 and base 16.
It is a nialpdrome in base 13.
It is a zygodrome in base 13.
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 549.
It is an amenable number.
549 is a wasteful number, since it uses less digits than its factorization.
549 is an evil number, because the sum of its binary digits is even.
The square root of 549 is about 23.4307490277. The cubic root of 549 is about 8.1882441101.
Adding to 549 its product of digits (180), we get a 6-th power (729 = 36).
The spelling of 549 in words is "five hundred forty-nine", and thus it is an aban number.