There is no such number. Every number can be multiplied by 3 and every number can be multiplied by 4.
Multiply by is the usual form. Multiply 3 by 4 to get 12. If there are several numbers being multiplied then multiply .... together may be used... multiply 3, 4 and 5 together to get 60.
-1
2 and 6 3 and 4
Divide 4 by 2, then multiply by 3 and then add 4
-7
-1
The numbers are 3 and 4
-13
3 5 4
1764
252
-17