yeah I know you did not ask!
I am currently watching a Great Courses series (we have a streaming subscription) called: Maya to Aztec: Ancient Mesoamerica Revealed. I was utterly fascinated by the unit on Mayan math. They used a based 20 system and only needed 3 symbols to represent all the possible numbers. It was a positional system like our decimal system and unlike Roman numerals. The professor said the joke was that they counted on their fingers and their toes. He then reinforced that it was a joke and went on to say that no one was quite sure why they came up with a base 20 system.
Obviously we all work with base 10, more or less daily. As a programmer I worked extensively with a base 16 system of math and symbology. I occasionally also worked directly in base 8 and base 2.
All which started me thinking about an Okie I once knew who invented a base 21 system. Of course, he was skinny dipping at the time he had this brain storm.