# [Brachylog], 8 bytes

    ọtᵒtᵍhth

[Try it online!][TIO-j4gqmgt8]

[Brachylog]: https://github.com/JCumin/Brachylog
[TIO-j4gqmgt8]: https://tio.run/##SypKTM6ozMlPN/r//@Hu3pKHWycBcW9GScb//4aWJhbmhgYmlhb/owA "Brachylog – Try It Online"

### Explanation

    Example input: 495902

    ọ          Occurences:    [[4,1],[9,2],[5,1],[0,1],[2,1]]
     tᵒ        Order by tail: [[0,1],[2,1],[4,1],[5,1],[9,2]]
       tᵍ      Group by tail: [[[0,1],[2,1],[4,1],[5,1]],[[9,2]]]
         h     Head:          [[0,1],[2,1],[4,1],[5,1]]
          t    Tail:          [5,1]
           h   Head:          5