How many Maccabees were there and what were their names?
Megillas Antiochus lists five sons of Matisyahu: Yehudah, Shimon, Yochanan, Yonasan, and Elazar.
I Maccabees has the same names, but in rearranged order: Yochanan, Shimon, Yehudah, Elazar, and Yonasan. (It also gives their respective nicknames or cognomens: respectively, Gaddi, Thassi, Maccabeus, Avaran and Apphus.)
Rashi (to Deut. 33:11) mentions "twelve sons of Chashmonai and Elazar," but doesn't give names.