Q: What is E.164 phone numbering format?
E.164 number uniquely identifies a public network termination point and typically consists of three fields, CC (country code), NDC (national destination code), and SN (subscriber number). As an international phone number format it can have up to 15 digits in total.
For example a phone number in USA, California will look like this +14155544000, a number in UK, London will look like +442079834000 and a number in Berlin, Germany can look like this +493090260 etc.
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