5. (10 points) There is a strange computer with a button. If the number on the computer is a multiple of 3, pressing the button will divide it by 3; if the number is not a multiple of 3, pressing the button will multiply it by 6. Xiao Ming pressed the button 6 times in a row without looking at the number on the screen, and the final number displayed on the computer was 12. What is the smallest possible number that was initially on the computer? $\qquad$
【Solution】Solution: $\because$ The final number displayed on the computer is 12,
$\therefore$ Before 12, it could be 2 or 36,
If the previous number is 36, then before 36 it would be 108, and before 108 it would be 324, in this case, the starting number would be quite large, which definitely does not fit the problem,

If the previous number is 2, then we have $12 \rightarrow 2 \rightarrow 6 \rightarrow 1 \rightarrow 3 \rightarrow 9 \rightarrow 27$,
$\therefore$ The smallest possible initial number on the computer is 27,
Therefore, the answer is 27.