Prefix Information
The prefix 521 is part of area code 484 serving Allentown, Pennsylvania.
This exchange contains 10,000 possible phone numbers (484-521-0000 through 484-521-9999).
Phone numbers with prefix 521 in area code 484. Location: Allentown, Pennsylvania.
The prefix 521 is part of area code 484 serving Allentown, Pennsylvania.
This exchange contains 10,000 possible phone numbers (484-521-0000 through 484-521-9999).