Here's something new I learned today!

Old Uyghur (not a direct ancestor of modern Uyghur) had a so-called anticipating counting system in which, from Erdal 2004,
"First stated is the digit as starting the count from the lower decade, then the higher decade is mentioned."

For example, '11' is literally "one-twenty", 𐰋𐰃𐰼 𐰘𐰃𐰏𐰃𐰼𐰢𐰃 bir yegirmi, not "one-ten". Likewise, '26' is 'six-thirty', 𐰀𐰞𐱃𐰃 𐰆𐱃𐰆𐰔 altı otuz, not "six-twenty".

Note that this isn't back counting from the higher decade. '26' is 'six-thirty', not 'four-thirty'.

In the earliest Orkhon inscriptions, all of the decades are counted this way, but in later Old Uyghur records, the decades above thirty get much more tame. So, while originally, '34' was 'four-forty'', 𐱅𐰇𐰼𐱅 𐰴𐰃𐰺𐰴 tört qırq, in later texts we find otuz artuqı tört ...

... ('thirty-its-remainder-four').

Interestingly, this system of anticipating tens and twenties survives in the last surviving descendant of Old Uyghur, viz. the Western #Yugur language of north-central China. E.g., where '26' was altı otuz ('six-thirty') in Old Uyghur, we ...

... still get aʰldı oʰdız ('six-thirty') in Yugur (at least in older speakers).

The Western Yugurs are probably last Buddhist Turks remaining in the world (just like their Old Uyghur ancestors), and form an ethnic unity with the (also Buddhist) Mongolic-speaking Eastern Yugurs.

References:
- Marcel Erdal, A Grammar of Old Turkic, Brill (2004).
- Martina Erica Roos, The Western Yugur (Yellow Uyghur) Language: Grammar, Texts, Vocabulary, PhD Dissertation @ Leiden University (2000).
- Talat Tekin, A Grammar of Orkhon Turkic, Indiana University (1967).

Oh wait, no. At least some of the South Siberian Turks (Tuvans, Altayans etc.) are also Buddhist I think.