The downloaded iTunes6464.exe file gives error not a valid Win32 application

I don't get it. I download the latest iTunes installation file for WIndows 64-bit (iTunes6464.exe), but when I launch it, I get the error message that it's not a valid Win32 application. Of course it's not. It's supposed to be a valid Win64 application. Anyone know why it won't install and why it gives this odd error message? How do I install the latest iTunes for Windows 64-bit?