Factorials

Concept Quizzes

Factorials Warmup
Trailing Number of Zeroes
Wilson's Theorem
Number Theory Step Up to Level 4 - Set 1

Challenge Quizzes

Factorials: Level 1 Challenges
Factorials: Level 2 Challenges
Factorials: Level 3 Challenges

Factorials Warmup

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

1

6! - 1

(6 - 1)!

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by Brilliant Staff

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.

3 4 5 There is no positive integer

n

such that

n!

has exactly 1 trailing zero

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by Brilliant Staff

What is the smallest value of $n$ such that $n!$ is divisible by $9?$

Note: If $n$ is a positive integer, $n! = 1 \times 2 \times 3 \times \cdots \times (n - 1) \times n.$ For example, $5! = 1 \times 2 \times 3 \times 4 \times 5.$

4

5

6

7

8

9

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by Brilliant Staff

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

Yes No

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by Brilliant Staff

$x! = 3! \times 5!$ What is $x?$

6 7 8 9

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by Brilliant Staff

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