The world's population is expected to hit 7bn on Monday and over on the Beeb's website, you can find out where in that number you came (well, approximately!). I am No. 4,027,375,590. It also transpires that I'm around the 78,362,899,628th person to have ever lived.
You can find out what your numbers are (along with some additional information about your own country's population and life expectancy), here.