Conversation so far:
who appeared on the $20 bill in 1875
1875 20 dollar legal tender notes have a portrait of Alexander Hamilton on one side of the bill.
What figure appears on the current 20 United States dollar bill?
The seventh U.S. president, Andrew Jackson, has been featured on the front side of the bill since 1928

Question: Who else has appeared on the bill?
Self-contained rewrite: Who else besides Alexander Hamilton and Andrew Jackson has appeared on the 20 dollar bill?