795-2222-10-21 is a phone number belonging to Concord, a city located in California. The first three digits, 795, identify the area code in which the phone number is based, which in this case is Concord's. The next four digits, 2222, are the local exchange, while the next two digits, 10, identify the specific geographic area in the local exchange. The last two digits, 21, are what is known as the line number, and is the unique number assigned to the individual phone line.