What other languages have unusual constructs, à la soixante-dix and quatre-vingts?
But if you like, I'll give you the Danish word for 70, "halvfjers", literally "half-fourish", meaning half way between three and four 20's.
Wow, there's an entire Wikipedia article on this with lots of interesting tidbits: https://en.wikipedia.org/wiki/Vigesimal#Europe
TIL. Thanks!
Numbers in Danish are a bit odd.
Of course this doesn’t mean that specific words (for example the numbers) may not have derived from or been influenced by other languages like Basque.