The duodecimal system (also known as base 12 or dozenal) is a positional notation numeral system using twelve as its base.
base 24
base 24 is a positional numeral system with twenty-four as its base. It uses 24 different digits for representing numbers. The digits for base 24 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, and n.