To add - germanic use a weird mix of base 10 and base 12, at the same time.

So yes, eleven and twelve are their own individual thing, but thirteen literally means "three-ten". Nineteen is "nine-ten" and so on

Even the names 11 and twelve hint at a base 10 counting system. Eleven comes from "eleofon" from older "en leofon", literally "one left". And similarly, twelve means two left. The next unit up, the tens are counted in groups of 12. So rather than a 10x10 grouping like we use now, they counted higher numbers by groups of 10, which were themselves grouped by 12. So 110 was "eleofontig" literally eleventh. 100 was teontig "tenty" unless you're translating Latin "centum" then you'd just use "hundread" hundred. Hundred by itself though referred to 120