On this BBC News World article,
7 billion people and you: What's your number? you can enter your date of birth and the web app will tell you where you fall (numerically) in the scheme of mankind.
When I was born, I was the 2,705,110,781st person in the world (living at that time).
That number -- 2,705,110,781 -- looked to possibly be a prime number. I was (not really) surprised to find there's an Excel function -- GCD -- which returns the greatest common divisor of the operand. It turns out that 2,705,110,781 can only be divided by one and 2,705,110,781, making it a prime number.
I'm not (quite) silly enough to think there's any cosmic significance with my 2,705,110,781st position in the population. After all, the web app didn't ask me what time I was born, or any of a number of other limiting factors.