Numbers / 80

The Number 80

80 is composite: factorization 2^4 × 5. That gives 80 exactly 10 divisors: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80. 80's proper divisors total 106, 26 more than 80 itself, so 80 is abundant. 80 has a digit sum of 8; for 80, the digital root works out to 8. 80: 2, 4, 5, 8, 10 all divide 80 evenly, out of 2-12. 80 is 1010000 in binary and 50 in hex; as a Roman numeral it's LXXX.