Final answer:
There are infinite cool numbers.
Step-by-step explanation:
A positive natural number is called cool if the number before it is one of its divisors. To find out how many cool numbers there are, we need to consider different scenarios.
If we start with the number 1, since it doesn't have any divisors before it, it is not cool. For any other positive natural number, it will always have 1 as one of its divisors, so all other numbers are cool.
Therefore, the answer is infinite.