Quote Originally Posted by LuxDefensor
Well, your "B" point is not actually about the numerals. "Тысяча", "миллион" etc are used as nouns
While of course you are correct, I was assuming that happyclogs was using the word "number" in the typical English sense. We consider “thousand/million/billion” numbers because they indicate a precise quantity, thus I wanted to reinforce that numbers, particulary when the number is in the nominative/accusatuve, are in fact not followed by the same case of the noun they quantify.

In essence we are saying the same thing, I just made a different assumption about what ‘number’ would mean to happyclogs.