Here is a simple nice command to figure out how many processors or cores are assigned to a *unix machine.
cat /proc/cpuinfo | grep processor | wc -l
This basically processes the lines containing the processor information and counts them up for you, I got 4. Try the same commands without the word count (wc) pipe and you can get much more information in detail.
cat /proc/cpuinfo | grep processor
By trying the above I got the following:
processor : 0 processor : 1 processor : 2 processor : 3
Try it even further without the grep for processor and you get lots of detailed information about your system. Try it out!