What is interesting about the factors of 220 and 284?

Answer 1

the factors of 220 add up to 284; the factors of 284 add up to 220.

220 is divisible by 1,2,4,5,10,11, 20,22,44,55 and 110.

1+2+4+5+10+11+20+22+44+55+110 = 284

284 is divisible by 1,2,4,71 and 142.

1+2+4+71+142 = 220.

A pair of numbers with this ability is called 'amicable numbers'.

Other knows pairs of amicable numbers are (17296, 18416) and (9363584, 9437056).

Answer 2

The factors of 210 are:

1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 35, 42, 70, 105, 210

The factors of 294 are:

1, 2, 3, 6, 7, 14, 21, 42, 49, 98, 147, 294