What is the patent number of the game football?
Football is not patented. The rules are readily available and anyone can play. Many items related to football have copyrights, such as the rule books, team names and recordings of games.
Patent pending is a warning that a patent application has been filed. It is completely worthless until and unless a patent is actually issued for that invention. Patent number notice means a patent with that number was issued for the invention that is implemented in the product labeled with that number.
If it is a U.S. patent, you can go to the USPTO website for patent searches and enter the number in "patent number search". You can obtain the online image of nearly any US patent ever issued (using TIFF format). If you do not know the patent number, you may have to go elsewhere for more information, as the USPTO database prior to 1976 cannot be searched by anything other than the patent number. http://www.uspto.gov/patft/index.html
A patent number will only tell you the EARLIEST date on which the device was manufactured, and the patent number could still be put on many years after the patent expired (although without any legal effect). For U.S. patents, go to USPTO.gov, click patent, search, and type in the number to find the image of the particular patent you're interested in (prior to 1976).