I’m in the lesson for scholar and in the first example sentence there is a part I don’t understand.かれのお父さんは、立ぱな学者です。

(His father is a splendid scholar.) I don’t understand the 立ぱな before scholar. Also I don’t know the reading of 立 in this instance either.

This is my first post so I’m not completely sure I am doing this correctly! Thanks in advance!!!