- #1

Kyuubi

- 18

- 8

There are only 4 natural numbers whose factorial contains the same number of digits as the number itself. That is to say n = digits_in(n!).

The trivial case is obviously just 1. 1! has only one digit. The other three are surprising, because they are consecutive.

They are 22, 23, and 24.

Unfortunately for our pal 25, it has 26 digits, and after 25, the number of digits begins increasing with an average >1 and the digits can't keep up with their mere increment of +1.

Just thought that was cool and wanted to share it.