From: John C Klensin <KLENSIN(_at_)infoods(_dot_)mit(_dot_)edu>
That's ok, telephone company country codes don't even equal country.
They are originally pairwise--the code that I dial to get from my
country to get to your country, which might differ from the code dialed
from another country to get to your country. There has been an effort
to rationalize this over the last few years so people can put phone
numbers into correspondence that will travel internationally, but the
list of exceptions is still quite impressive.
The prefix you dial before the country code varies but the contry
codes themselves are fixed no matter where you dial them from. (Of
course, North America has this pseudo country code "1" and there are
"countries" like Vatican City which use the code of a surrounding
country.) That is why the standard form for writing an international
number is <plus sign><country code (two or three digits except for
"1"><space> <rest of number with whatever spaces or hyphens you wish>.
Thus my work number is +1 508 486 2358 where the + translates to 011
or 01 in the US but could be any bizarre sequence in other places.
Donald