They are: 1, 2, 7 and 14
(1, 72) (2, 36) (3, 24) (4, 18) (6, 12) (8, 9)
(14,1)(7,2)
1 and 28, 2 and 14, 4 and 7.
The factor pairs of 51 are (1,51) and (17,3)
The difference is between factor pairs and distinct factors. With square numbers, one of the factor pairs will be the same number twice. When listing the distinct factors, that number is only listed once.
The factor pairs of 14 are 1*14, and 2*7
14 = 1*14, 2*7 14 = 1 x 14 ( 1st factor pairs) = 2 x 7 (2nd factor pairs
The factor pairs of 28 are 1*28, 2*14, and 4*7
(1, 72) (2, 36) (3, 24) (4, 18) (6, 12) (8, 9)
(1, 14) (2, 7)
1 and 14, 2 and 7
(14,1)(7,2)
14 = 1 x 14 14 = 2 x 7
The factor pairs of 112 are 1*112, 2*56, 4*28, 7*16, and 8*14
The factor pairs of 56 are: 1, 56; 2, 28; 4, 14; 7, 8 Therefore, if you exclude itself and 1, there are three factor pairs, but if you include itself and 1, there are four factor pairs.
There are five factor pairs for 196:196 = 1 x 196196 = 2 x 98196 = 4 x 49196 = 7 x 28196 = 14 x 14
The factor pairs of 56 are 1 x 56, 2 x 28, 4 x 14, and 7 x 8.