Number between 1 and 20 that has 5 factors

16 because the factor of 16 are 1,2,4,8,16

16 because the factors are 1,2,4,8,and16

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.