A Number System Invented by Inuit Schoochildren
The Alaskan Inuit language, known as Iñupiaq, uses an oral counting system built around the human body. Quantities are first described in groups of five, 10, and 15 and then in sets of 20. The system “is really the count of your hands and the count of your toes,” says Nuluqutaaq Maggie Pollock, who taught with the Kaktovik numerals in Utqiagvik, a city 300 miles northwest of where the numerals were invented. For example, she says, tallimat—the Iñupiaq word for 5—comes from the word for arm: taliq. “In your one arm, you have tallimat fingers,”
It's available (soon) in unicode:
Thanks to efforts by linguists working with the Script Encoding Initiative at the University of California, Berkeley, the numerals were included in the September 2022 update of Unicode, an international information technology standard that enables the digitization of the world’s written languages. The new release, Unicode 15.0, provides a virtual identifier for each Kaktovik numeral so developers can incorporate them into digital displays.