This is the 108th most frequent Italian word.
molti
"Molti" means "many" in English.
In this sentence, 'molti' is used as an adjective to describe 'libri', indicating a large quantity.
Ci sono molti libri sulla scrivania.
There are many books on the desk.
Here, 'molti' is used as a pronoun to refer to a group of people implicitly defined.
Molti credono che questo sia vero.
Many believe this to be true.
In this case, 'molti' is again an adjective that qualifies 'regali', expressing a significant number.