Chabad.org — English translation + Rashi
Torah Temimah: “רבבות אלפי ישראל” — the phrase measures Israel as myriads of thousands, the scale of the camp under the cloud.
English: “Myriads of thousands of Israel” — the measure of the camp.
Scale of the people — the prayer names Israel by its multitude.
Hashem is asked to dwell with a nation counted in the tens of thousands.