Historically, the most convenient are numbers with large numbers of factors. 60 can be split into 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 evenly for example The oth

Historically, the most convenient are numbers with large numbers of factors. 60 can be split into 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 evenly for example The other number that accomplishes this is 12: 2, 3, 4, 6 are all factors. That's why 12 and 60 are so common for real life systems.