The most common and most likely answer to this crossword clue is the 6 letter word SWARMS
S
W
A
R
M
S
Buddy explains!

The straight part
We know that "Huge numbers" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case huge numbers = swarms.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SWARMS mean?
SWARMS noun- A large number of insects, especially when in motion or (for bees) migrating to a new colony.
- A mass of people, animals or things in motion or turmoil.
- A group of nodes sharing the same torrent in a BitTorrent network.
- To move as a swarm.
- To teem, or be overrun with insects, people, etc.
- To fill a place as a swarm.
- To overwhelm as by an opposing army.
- To climb by gripping with arms and legs alternately.
- To breed multitudes.