At first I thought you might've slightly leaked your phone number here, but there's surprisingly many 10 digit prime numbers with a triple-7 in the middle (and

At first I thought you might've slightly leaked your phone number here, but there's surprisingly many 10 digit prime numbers with a triple-7 in the middle (and obviously that inner 777 can't be next to a 7 else you'd call it a quadruple-7 [etc]), 1905394. If you filter on only valid area codes, the number is a bit smaller (620350), and if you exclude Toll Free, Reserved, and Government area codes it's down to 567277.