Numbers / 642
The Number 642
642 is composite: factorization 2 × 3 × 107. That gives 642 exactly 8 divisors: 1, 2, 3, 6, 107, 214, 321, 642. 642's proper divisors total 654, 12 more than 642 itself, so 642 is abundant. 642 has a digit sum of 12; for 642, the digital root works out to 3. 642: 2, 3, 6 all divide 642 evenly, out of 2-12. 642 is 1010000010 in binary and 282 in hex; as a Roman numeral it's DCXLII.