U.S. Open - How many tennis players try to qualify and how many actually do so?

I'm trying to get some information about the U.S. Open. How many players try to qualify? How many successfully get to play in the tennis tournament? Thanks!

bromothymo:
The men's and women's U.S. Open singles qualifying draws start with 128 players, same as the main draws. They play from Tuesday through Friday, the week before the main tournament begins. Qualifiers play one match a day, and the final 16 from each draw compete in the main tournaments.
Often overlooked, is the fact that the qualifying tournament is an event in and of itself. It offers quite a bit in prize money- over one million dollars. It can also be a "launch pad" for up and coming stars.
The men's doubles qualifying draw only starts with 16 teams. Of those, 4 will gain acceptance into the main draw. Same rules for the women.

shanti804:
I believe that 64 men and 64 women qualify for any of the opens.