This reminds me of this old Feynman video where he talks about how people use different methods in their heads when counting, seems relevant: https://youtu.be/Cj4y0EUlU-Y?t=135
Love it! I use something similar to remember long numbers. If a code or a pin has let's say 8 digits, I'm unable to remember it the normal way. So I remember the first digit in the inner voice, and the other 4 digits as a picture of the digits.
+ Rudolph Flesh, The Art Of Clear Thinking (1951). He has visualizations in there how people concepualize the months in a year as an ellipsis, and so on.