Why didn't the phone companies change the length of the phone numbers for new applications like faxes?

1. Why are some phone numbers longer?
2. What happens if you call a fax number?
3. How don't they run out of phone numbers?
4. Why are phone numbers the way they are?

Why are some phone numbers longer?

An Over-spell is a phone number that uses extra phantom digits to complete the spelling of a word. For example 1-800-ESURANCE (1-800-378-7262), the word ESURANCE is a vanity number with 8 characters (1 extra). In these cases, the additional number(s) can be dialed without influencing the call in any way.

What happens if you call a fax number?

Can You Call a Fax Number? Generally, it is possible to call a fax number. When calling a fax number with a normal phone, you will hear a set of beeps produced by the receiving fax machine. The beeping sound is called a handshake signal which is used to establish an agreement between two fax devices.

How don't they run out of phone numbers?

There are 10 Digits in a US phone number. Each Digit has a possibility for 10 combinations 0-9, and order matters. This means that there are 10^10 possible phone number combinations 10,000,000,000 or 10 billion possible numbers.

Why are phone numbers the way they are?

The first three digits are the area code, which refers to a broad geographic region. The next three digits denote the prefix, which typically corresponds to a smaller area within the area code's region. With four remaining digits every local exchange has 10,000 possible unique numbers (from 0000 to 9999).