The least common factor of any set of positive integers is 1.
560 280,2 140,2,2 70,2,2,2 35,2,2,2,2 7,5,2,2,2,2
103 is prime, so it's only factors are 1,103
83 is prime. No tree.
61 is already prime. It doesn't need a tree.
Factor Tree of 612: ..........612 ............/ \ ........12 * 51 ......../ \ ......6 * 2 ...../ \ ...2 * 3 Prime factorization of 612 = 2 * 2 * 3 * 51
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
6122, 3062, 2, 1532, 2, 3, 512, 2, 3, 3, 17
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
The GCF of 15 and 612 is: 3
253 11,23 Not much of a tree. More like a factor shrub.
612 306,2 153,2,2 51,3,2,2 17,3,3,2,2
214 2,107
It's 35