1)
Do the numbers mentioned here, and in Pesukim 9,16,24,31, 32 refer to another census?
1.
Ramban: No! they are all part of Hashem's command to Moshe and Aharon in Pasuk 1, where Hashem already informed them how many each Degel would comprise when they traveled. 1
1
Ramban: And the Pasuk is coming to teach us the tremendous miracle that took place here, inasmuch as, bearing in mind the over half a million men involved, during the 20 days between the command (on the first of Iyar) and the actual traveling (on the twentieth), not a single person died.