First, we must lay out all the factors of 3150 and they
are:
1, 2, 3, 5, 6, 7, 9, 10, 14, 15, 18, 21, 25, 30, 35, 42, 45,
50, 63, 70, 75, 90, 105, 126, 150, 175, 210, 225, 315, 350, 450, 525, 630, 1050,
1575, 3150
Among these numbers, the only perfect square are:
9, 25, 225