I figured out a way to remember a 52 digit pw easily enough recently, using just my immediate family members' birthdays (which I've memorized since childhood anyways - mixing in spouse and children work work as well), separated by special characters in a memorized sequence.
Ex: the start might be Mom022759@+Dad100855#+Jill071779$+... Even if the birthdates were public record and hackable, the methods of mixing in special characters would be unique or meaningful only to the user. In this example the separating characters are just going down the keyboard, 2, 3, 4... Works like a charm!