telephoneNumber

A telephonenumber is the numeric address assigned to a subscriber or service endpoint in a telephone network. It is used to route calls, deliver messages, and access various telecommunication services. Numbers are allocated by national or regional numbering authorities and may be associated with individuals, devices, organizations, or services such as VoIP.

International notation follows the E.164 standard developed by the International Telecommunication Union (ITU). An international telephonenumber comprises a country code, followed by a national significant number, and is typically written with a leading plus sign. The maximum length of an E.164 number is 15 digits, excluding formatting characters. For example, [phone]. Domestic formats vary by country; when dialing within a country, the country code may be omitted in favor of local area and subscriber numbers.

In computing and data management, telephonenumbers are often normalized to E.164 for interoperability. Validation commonly enforces a numeric sequence of up to 15 digits after removing spaces, hyphens, and parentheses. The national component can include area codes and mobile prefixes, while emergency numbers and short codes may be defined separately by national authorities.

Privacy and security considerations include potential exposure of personal contact information, theft, or spoofing. Carriers and regulators govern handling of numbers, and features such as number portability let users retain a telephonenumber when changing providers. Telephonenumbers also appear in directories, caller-ID systems, and billing records.