A factorial is the product of all positive integers up to a given number (n!).
✓ TRUE FACT
Factorials grow insanely fast: 10! = 3,628,800 and 20! ≈ 2.43×10^18. They show up everywhere from counting permutations to probability and series expansions.
🤯 "A factorial is the product of all positive integers up to a given number (n!) — the math version of escalating commitment."