It might be different in various countries.. Here's part of the history for the USA: http://www.privateline.com/mt_telecomhistory/b_letter_prefixes_or_exchange_names/
Five digit- four digit
There are 120 of them. Here are five: 1,357 3,579 5,791 7,913 9,135
Four to the first power is four. Any number to the first power is that number.
four
The sum of the first four prime numbers is 17.
210 is the number whose prime factors are the first four primes unrepeated.
"hola", "alo", "bueno" In Spain (not Latin America) the most used word to answer a phone call is "Diga" or "Dígame" To ask for a telephone number you would say ¿Cuál es tu número de teléfono? To tell what your telephone number is you must say the numbers individually one after another, this way nine three (or ninety three, because it is the prefix) four-five-one-six- eight-four-two (this is an example)
Any real number to the first power is the number itself.
YES. YES.
3347
the first number needs to be four.
the second pair of three numbers before the set of four numbers for example 386->249<-5484 ps this number is a fake number so dont call it lol