Waste less time on Facebook — follow Brilliant.
Back to all chapters


2! = 2, 3! = 3*2, 4! = 4*3*2… and 100! is a lot better than writing out 158 digits. 90! is the largest factorial that can fit in a tweet.

Factorials Warmup


Which of the following is equal to \(\Large \frac{6!}{6}\)?

What is the smallest positive integer \(n\) such that \(n!\) has exactly 1 trailing zero?

Note: Trailing zeros are sequences of zeros that come at the end of a number. For example, 1,000 has 3 trailing zeros and 1,001 has no trailing zeros.

What is the smallest value of \(n\) such that \(n!\) is divisible by 9?

Are there 3 consecutive positive integers whose product is not divisible by \(3! \, ?\)

\[x! = 3! \times 5!\] What is \(x?\)


Problem Loading...

Note Loading...

Set Loading...