What are the factors of (r+t) (e)

Depending on the values of 'r', 't', and 'e', the numerical value of that expression

might have many factors.

For example, if it happens that r=5, t=1, and e=4 for an instant, then, just

for a moment, (r + t) (e) = (5+1) (4) = 24, and the factors of (r+t) (e) are

1, 2, 3, 4, 6, 8, 12, and 24. But that's only a temporary situation.

The only factors of (r+t) (e) that don't depend on the values of 'r', 't', or 'e',

and are always good, are (r + t) and (e).