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Number Theory/International Country Telephone Codes.

Question
Dear Prof Scott

http://countrycode.org/
http://www.countrycallingcodes.com/
http://en.wikipedia.org/wiki/Telephone_numbering_plan
http://en.wikipedia.org/wiki/International_Telecommunication_Union
http://www.iucnredlist.org/technical-documents/data-organization/countries-by-re

We have different international telephone codes for every country.
There are 196 countries in the world.

Some examples :

UK : 44
India : 91
Russia : 7
Netherlands : 31

How those standards were set for each telephone country code by the International Telecommunications Union (ITU) ?

i.e. Is the Number codes given as per country names alphabetical sorting i.e. Afghanisation, Albania, Algeria etc
i.e. Afghanisation = 1, Albania = 2, Algeria = 3, but looks like this may be not the case as USA = 1.

Statistical analysis for the International Telephone codes
----------------------------------------------------------

1.Min and Max Numbers

USA : 1  - Min Number
Uzbekistan : 998 - Max Number.

2. Telephone Code Sorting - Ascending Order

USA : 1
Kazakhstan, Russia : 7
Egypt : 20
Greece : 30

etc

3.Telephone Code Sorting - Descending Order

Uzbekistan : 998
Kyrgyzstan : 996
Georgia : 995

etc

Was a Random number selected for every international country telephone code for the standards ?

Some of the Whole Integer Numbers are not taken into account for example 2,3,4,5,6,8,9,10,11 etc. i.e. they are skipped.

International telephone codes were given on the basis of Grouping of countries region wise viz Africa, Asia, Europe, America, Antarctic ?

Thanks & Regards,
Prashant S Akerkar

I have no clue how they picked telephone numbers.

All that I know is the more populated countries tend to have lower numbers.
Since the USA started the phone system and long distance started with a 1,
that is still what it is.  Since Russia was kind of important, they also have a single number,
and that is 7.  China may have a high population, but they are only now developing technology.

Of the countries at the bottom with three digits, they are small and unheard of.

As far as why certain numbers were skipped, it most likely had something to do with the phone system and how calls are processed.

For example, most calls that were local only use 7 digits ( a few years ago, it was only 5).
If they are long distance, they need a 1 and 10 more digits, and most often the first three digits after the 1 had a zero in the middle.

When I was growing up, I'm not sure it was possible to call another country.  In fact, many countries in the world didn't even have telephones.  Speaking of technology, the computers we had took up entire buildings and use massive fans to keep them cool in the 1970's.  PC's came out in the mid 80's, so I bought one with 256K of internal memory back in 1985 for around \$2000 when the minimum wage was only \$3/hour.  It also could take 2 floppy drives that were a little over 5" square and very thin, so they had to be handled carefully.

Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Dear Prof Scott Thank you. Thanks & Regards, Prashant S Akerkar

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