256 bits

Let m=2^256.

57! < m < 58! (Let 58 people in a ring remember who they stood next to?)

(Note: 2^224 < 52! < 2^225 for permutations of a deck of cards.)

2^256 is approximately 10^77.

55 letters of the alphabet

Choosing, in any order, 131 items out of 262.

Choosing, in order, 26 items out of 933 (=31*31).