You need to be at least 18 years and a legal US resident (You are certainly eligible provided your status is clean!!). Don't expect the full amount you won. For your case, you would have pay around 28-33% tax (It varies state to state).

BTW, the first rule after wining a lottery is not to tell everyone you did!!! Rather than posting a thread in Sajha, Google around about what you have to do after wining a lottery to be on a safe side. You must have heard news about people killing their friends for a mere 6000 Rs. worth of cell phone and out here in America, we certainly don't have a scarcity of those type of mofos!!! Enjoy till it lasts brother!!