The first 15 multiples of 252:
252, 504, 756, 1008, 1260, 1512, 1764, 2016, 2268, 2520, 2772, 3024, 3276, 3528, 3780 . . .
252, 504, 756 . . .
252, 504, 756 and so on.
There are infinitely many of them so they cannot be listed. One of their multiples is 294*252*210 = 15558480.
The first 15 multiples of 252: 252, 504, 756, 1008, 1260, 1512, 1764, 2016, 2268, 2520, 2772, 3024, 3276, 3528, 3780 . . .
252
252 and its multiples.
84, 168, 252 and so on.
126, 252, 378 and so on.
84, 168, 252.
Any multiple of 252.
84, 168, 252
No, they are factors.