base 31 is a positional numeral system with thirty-one as its base. It uses 31 different digits for representing numbers. The digits for base 31 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, and u.

base 27 is a positional numeral system with twenty-seven as its base. It uses 27 different digits for representing numbers. The digits for base 27 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, and q.