John Gill Commentary Numbers 2:9

"All that were numbered of the camp of Judah were a hundred thousand and fourscore thousand and six thousand and four hundred, according to their hosts. They shall set forth first." — Numbers 2:9 (ASV)

All that were numbered in the camp of Judah [were] an hundred
thousand and eighty thousand and six thousand and four hundred ,
throughout their armies
186,400 men. The sum total of the three tribes, which formed that camp: this was the largest camp of them all, being near 30,000 more than Dan's, (Numbers 2:31) , which was the next in number to it, and therefore placed foremost, and as the vanguard to the tabernacle:

these shall first set forth ;
in a march, when about to journey; when they saw the cloud remove, the priests blew with the trumpets, and then the camp of Judah moved first, as Jarchi observes, and when they went out to fight, Judah went up first, (Judges 1:1Judges 1:2) .