Sumerians used sexagesimal numerals not only because the number 60 has many divisors or it is countable on the fingers of both hands but because 60 is the least common multiple of the number of fingers of both hands and the number of months in a year. The Chinese cycle of the Stems and Branches has the same structure as the Sumerian sexagesimal system and we can assume the Chinese sexagesimal cycle was imported from Mesopotamia to China. Today both the Mesopotamian sexagesimal system and the Chinese sexagenary cycle are apt to be explained in terms of the 60-year conjunction cycle of Jupiter and Saturn, such an interpretation of posterity should not conceal the original implication.