One number is afactor of another if the first number divides into the second a whole number of times. For example,6 is a factor of42=6×7but 8 is not afactor of 28 as 8 into 28 goes 3 times with a remainder of 4. The property of having many factors is a handy one to have for the base of your number system, which is why twelve mayhavebeen abetter choice than ten for our number base as 12 has 1,2,3,4,6, and 12 as its list of factors while 10 is divisible only by 1,2,5, and 10.