Numbers 1:47

The Levites, however, were not numbered among the sons of Israel, just as Yahweh had commanded Moses.

“Number the sons of Levi by their fathers’ households, by their families; every male from a month old and upward you shall number.”

According to the word of Yahweh by the hand of Moses, they were numbered, everyone by his serving or carrying; thus these were his numbered men, just as Yahweh had commanded Moses.

And those who were numbered of them were 23,000, every male from a month old and upward, for they were not numbered among the sons of Israel since no inheritance was given to them among the sons of Israel.

Levites Not Numbered in the Census