Strip Phone Numbers Down to Digits

You're a customer-support analyst loading 12 phone numbers into a dialer that requires digits only — no parentheses, no dashes, no dots, no spaces. The source data uses mixed formats: (555) 123-4567, 555.987.6543, 555-555-1212, 555 444 3333, etc.

Your task:

1. In column B (Digits), write a formula that strips every non-digit character from each phone string and returns the digits-only numeric value. Most rows produce a 10-digit result; rows with a leading country code (e.g. +1 800 555 1212) produce 11 digits — the formula should handle both without special-casing.
2. The formula must drag-fill from B2 → B13.

The two acceptable patterns:

• REGEXREPLACE (recommended): =VALUE(REGEXREPLACE(A2, "[^0-9]", "")) — one regex replaces all non-digit characters; VALUE coerces the result to a number.
• SUBSTITUTE chain: five nested SUBSTITUTEs to strip (, ), -, ., and space individually, then VALUE.

Graded cells: B2 ((555) 123-4567 → 5551234567), B5 (212.555.0199 → 2125550199), B9 (+1 800 555 1212 → 18005551212).