I was surprised to see Danish so high on the list, but after a short while it's not too surprising. It's base-20 for the first 20, like English. Then it's backwards base-10 up to 99 with special names for the whole 10s, 42 is pronounced as "2 and 40". Above 99 it's base-10, 420 is "400 20". But if it's 428 it's "400 8 and 20", but 512 would be "500 12". It's not difficult, it's just a special rule for 1-20, backwards for 21-99, and then straight as you'd expect (including the irregular first 20). Okay, it is quite confusing for none native speakers. To our defense, we use a system more like the Norwegian and Swedish for formal documents including contracts and cheques, though the latter has been phased out in Denmark.
The "perfect" would obviously be a purely base-10 with suffix if it's 10's, 100's, ect.
That's nearly exactly how german works, 428 is "4-vier 100-hundert 8-acht and-und 20-zwanzig", 512 is "5-fünf 100-hundert 12-zwölf" (excuse my rusty german). The und thing is a germanic thing I think.
"Und" is "and" in English, and "og" in Danish, and is used in Danish as well. I think Danish and German is quite similar as you say. It's been 20 odd years since I learned to speak German and it's long since forgotten.
The "perfect" would obviously be a purely base-10 with suffix if it's 10's, 100's, ect.