Numbers / 75

The Number 75

75 is composite: factorization 3 × 5^2. That gives 75 exactly 6 divisors: 1, 3, 5, 15, 25, 75. 75's proper divisors total just 49, 26 short of 75, the deficient case most of 75's neighbors share too. 75 has a digit sum of 12; for 75, the digital root works out to 3. 75: 3, 5 all divide 75 evenly, out of 2-12. 75 is 1001011 in binary and 4B in hex; as a Roman numeral it's LXXV.