1 is the only one i think...
One.
Nothing.. Because 21 is a Prime number
There is no number that goes into both. must be a trick questionthis is another person not the same one :)the number that goes into 12 and 21 is 3 which is a 5th grade problemwho ever said theres no number that goes into 12 and 21 is WRONG!
The number is 1.
It is 21 minus 100 = -79
It is the number 1
21 is composite number because it has more than one number that goes into it
No even number gose in 21. In fact there is none that goes in 21, either.
The factors of 158 are 1, 2, 79, and 158.
The number is 1.
7
It is 1