Produce a long descriptive sentence that uses all these words: AEK Athens F.C. LEAGUE Superleague Greece; Superleague Greece CHAMPIONS Olympiacos F.C.; AEK Athens F.C. GROUND Athens; AEK Athens F.C. NUMBER_OF_MEMBERS 69618
AEK Athens F.C.'s ground is in Athens and they have 69618 members . They play in the Superleague of Greece of which Olympiacos FC are previous champions.