1. The problem is to find the factorial of a number, which is the product of all positive integers up to that number. 2. The factorial of a number $n$ is denoted as $n!$ and is defined as: $$n! = n \times (n-1) \times (n-2) \times \cdots \times 2 \times 1$$ with the special case $0! = 1$. 3. For example, to find $5!$: $$5! = 5 \times 4 \times 3 \times 2 \times 1 = 120$$ 4. Factorials grow very fast and are used in permutations, combinations, and other areas of mathematics. 5. If you provide a specific number, I can calculate its factorial for you.