Does anyone know of a website that could verify whether HSBC Bank of Hong Kong is fraudulent or not?

I've been entering in online lotteries for taking surveys these last few weeks. Recently, I received a cordially written email from "HSBC Bank of Hong Kong" asking for my account number and identification in order to receive my interest of $800,000 from the lotteries. I replied back asking if there were a number I could contact them at and they replied with several numbers and an address. The thing is that I cannot call it because it is a Hong Kong number. The rule of thumb over the internet is to never give your personal information out...especially when it comes to something like this. As I still remain very skeptical, it still couldn't hurt to find out a little about this. What is a good source for determining the legitimacy of something like this? Please help!!!