Numbers / 145

The Number 145

145 is composite: factorization 5 × 29. That gives 145 exactly 4 divisors: 1, 5, 29, 145. 145's proper divisors total just 35, 110 short of 145, the deficient case most of 145's neighbors share too. 145 has a digit sum of 10; for 145, the digital root works out to 1. 145: 5 all divide 145 evenly, out of 2-12. 145 is 10010001 in binary and 91 in hex; as a Roman numeral it's CXLV.