33 is nontrivially palindromic in base 2 and base 10.
33 is an esthetic number in base 7, base 15 and base 16, because in such bases it adjacent digits differ by 1.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is a nude number because it is divisible by every one of its digits.
33 is an idoneal number.
It is a D-number.
It is a Curzon number.
33 is a lucky number.
33 is a nontrivial repdigit in base 10.
It is a plaindrome in base 5, base 7, base 9, base 10, base 12, base 13, base 14 and base 15.
It is a nialpdrome in base 6, base 8, base 10, base 11 and base 16.
It is a zygodrome in base 10.
It is an amenable number.
33 is a wasteful number, since it uses less digits than its factorization.
33 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 14.
The square root of 33 is about 5.7445626465. The cubic root of 33 is about 3.2075343300.