You can obviously skip over all the prime numbers. Take 4, 6, 8, 9, 10, 12, 14, etc.
4 only has two proper divisors: 1, 2
sum = 3
6 has three: 1, 2, 3
sum = 6
8 also has three: 1, 2, 4
sum = 7
10 has three: 1, 2, 5
sum = 8
12 has five: 1, 2, 3, 4, 6
sum = 16
12 is the least abundant integer.
