Köshur number system is kinda weird (for academics).
Well, it's fine for day-to-day conversations. But, I recently tried using Köshur numerals while learning math. It's quite unintuitive when you look at what's written and what's being spoken. For example:
| Numeral | English | Köshur |
|---|---|---|
| 6 | six | shĕ |
| 7 | seven | sath |
| 67 | sixty-seven | satühöṭh |
I personally find English and Persian number systems more intuitive for modern math, as you don't have to mentally flip the numbers while reading them. Although the Sanskrit and Köshur numbers have had their advantages, I'd say those were mainly related to the way math was done in Sanskritic traditions (origin of the decimal place-value, consistent 10s, etc.). Currently, they don't seem to help much. English and Persian numbers seem quite straightforward w.r.t. writing and speech.
If we could do something similar for our numbers, they might be easier to learn and use in mathematical contexts because the spoken order would match the written notation.
| Numeral | English | Sanskrit | Persian | Köshur (+ hypothetically?) |
|---|---|---|---|---|
| 0 | zero | śūnya | sefr | siphar |
| 1 | one | éka | yek | akh, kun |
| 2 | two | dvi | do | zü |
| 3 | three | trí | se | trĕ |
| 10 | ten | daśa | dah | dah |
| 11 | eleven | éka-daśa | yāz-dah | kah / (kuni-dah?) |
| 15 | fifteen | panca-dasa | pānz-dah | pandah / (pāntsan-dah?) |
| 19 | nineteen | náva-dasa, ékonaviṁśati | nūz-dah | kunü-wuh / (navan-dah?) |
| 20 | twenty | vimśati | bist | wuh |
| 21 | twenty-one | éka-viṃśatiḥ | bist-o-yek | aküwuh / (wuhan-kun?) |
| 67 | sixty-seven | saptashashtiḥ | shast-o-haft | satühöṭh / (shēṭhan-sath?) |