How many not numbers are there?
There are infinite not numbers, nondenumerably so.
How many
numbers are there?
The answer depends on the kind of number. If you are talking about integers (3, 85,104,17, etc), for example, then that quantity is denumerably infinite. If, on the other hand, you are talking about real numbers (2.6, 17.785, 2678.91, 0.0034, etc.), then that quantity is nondenumerably infinite.
Denumerable means discrete, or countable, whereas nondenumerable means nondiscrete and uncountable. Nondenumerably infinite is infinitely more infinite than mere denumerably infinite.
The set of real numbers is comprised of two sets of numbers, 1) rational numbers and 2) irrational numbers. The rational numbers are denumerably infinite while the irrational numbers are nondenumerably infinite. Ergo, the set of real numbers is nondenumerably infinite, owing to the irrational numbers.
Roughly.