The 787-521 exchange is serviced by the following companies within the SANTURCE ratecenter.
CENTENNIAL PUERTO RICO OPERATIONS CORP. - PR
Call are routed trough OCN 8305 and CLLI - GUYNPR05DS0 (Common Language Location Identifier Code) and Point of Interface (POI) switch which is located in GUAYNABO.
Who's number is 787-521 Numbers?