A     844 - Area Number: The first three digits in ones Social Security indicates the location of the individual,  when the card was issued. There are no valid numbers that start with 750 or higher. B     78 - Group Number: In relation to the Area Number, the Group Number can indicate about when the Social Security Number was issued. In each area, odd numbers below ten and even numbers above ten are used first. After all are used up, even numbers under ten and odd numbers above ten are used. C     8486 - Serial Number: This number use to be assigned by local field offices until 1972, when the Social Security Administration centralized its offices. They are to issued chronologically, but this is not always the case.     SSN do not use a check digit scheme. More Information on Social Security Numbers can be found at the following sites: Government Social Security Site