Numbers / 33

The Number 33

33 is composite: factorization 3 × 11. That gives 33 exactly 4 divisors: 1, 3, 11, 33. 33's proper divisors total just 15, 18 short of 33, the deficient case most of 33's neighbors share too. 33 is also a palindrome, since 33 reads identically forwards and backwards. 33 has a digit sum of 6; for 33, the digital root works out to 6. 33: 3, 11 all divide 33 evenly, out of 2-12. 33 is 100001 in binary and 21 in hex; as a Roman numeral it's XXXIII.