The area code 623 is for the west side of metro Phoenix, Arizona, including Glendale.
It was created in 1999 when it was determined that just one area code (602) was not sufficient to service all of the Phoenix metropolitan area. Two new area codes were added: 623 and 480.
The 623 area code covers Peoria, Sun City, Sun City West, El Mirage, Surprise, Youngtown, Avondale, Tolleson, Goodyear, Buckeye, and most of Glendale, as well as some of west Phoenix, specifically the city north of Union Hills and west of the 2000 E Grid, south of the Arizona Canal from 43rd Ave to 39th Ave, west of 39th ave from the Arizona Canal south to Maryland Ave, along 43rd Ave from Maryland to Indian School, diagonally southwest from 43rd Ave & Indian School to 63rd Ave & Interstate 10, then south along 63rd Ave to the Salt River and then the Gila River Indian Reservation.
Most of Phoenix proper is still area code 602.
Area code 480 covers the eastern Suburbs (Mesa, Gilbert, Chandler, etc.) and the Phoenix neighborhood of Ahwatukee.
All calls within or between area codes 602, 623, and 480 are local calls.
623
Here are a couple of MSN access numbers, be sure to check if they are local or long distance for you: (602)528-4764; (480)429-2444; (602)282-1193.
It is 0.7*600 = 420
only 1 and 623. 623 is not divisible by any number
409 + 623 = 1032
623
623
191
-81 + 623 = 542
3% of 623 is 18.69
1000 - 623 = 377
623 is rounded to the nearest unit.