3. A certain digit a, greater than 1, was written on the board. The given number can be multiplied by 5 or the original single-digit number $a$ can be added to it. After several such
operations, the number 9859510 was obtained. Find $a$. If there are several possible options, list them in any order separated by a semicolon.
Answer: $5 ; 2|2 ; 5| 5,2 \mid 2,5$

## Examples of answer notation:

#