Answer:
189: 3 * 3 * 3 * 7 I think this is what you mean. If not, leave a note.
Explanation:
189: Can be factored. If the digits when added come to something divisible by 3 then the whole thing is divisible by 3
189: 63 * 3 Break the 63 down
63: 9 * 7 Break the 9 down
63: 3 * 3 * 7 Put 63s factors into 189
189:3 * 3 * 3 * 7