Besides perfect numbers and amicable numbers there are also sociable numbers. Same concept other than there's more than two in the sequence of numbers before getting back to the first number. For instance there's a 5 number sequence which starts with 14,296 which leads to 14288, 15472, 14536, 14264 and back to 14,296. The longest sequence found is of 28 numbers.
The vast majority of numbers just result in getting to 1. For instance:
100 - 1,2,4,5,10,20,25,50 totals 117
117 - 1,3,9,13,39 totals 65
65 - 1,5,13 totals 19
19 is a prime number so the only divisor is 1