Nobody understands, what the (0) in brackets in a telephone number means.
So please do not use it, just do not use brackets in phone numbers. No machine understands brackets neither. You cannot push a button with ( or ) on a telephone, nor dial them on rotary phones.
The dialling system has to understand where you want to end up with your call. It does not guess.
Status 2024. In Europe you may still be able to call an old fashioned number like 623168 just as it is. But that works, if it works at all, only within your area, the same area of caller and called. For example: In Bonn, German area code 0228, I can call locally (!) dial 211035 or (as from anywhere else in Germany) 0228 211035. It will ring the same number. Cost the same.
In Italy things (zeroes) are different. Italy always had more mobile phones then fixed lines, even back in the past 20th cenutury: « più telefonini che linee fisse ». So the increasingly rare fixed numbers must always be dialled with the area code and its leading zero. That immedialtely allows a lot more local numbers, those starting with 0, like 096690, which has to be dialled as 0471 096690 in any case. Local numers with a leading 0 effectively are newer numbers.
Let’s look at a Café: It advertizes +39 340 212 9431. This is a mobile number by Vodafone, +39 Italy. All italian mobile numbers start with 3.
A bank gives +39 0471 946511 as its number. This is a fixed phone line in Bolzano-Bozen, South Tyrol. In Italy you call this numer by dialling 0471 946511; just do not forget the leading 0 (zero)! From out of Italy you’d call this bank as 0039 0471 946511, or, if you can dial a plus sign +39 0471 946511.
Saluti!
Permalink to here:
https://blogabissl.blogspot.com/2024/08/international-dialling-in-italy-022.html
See also https://en.wikipedia.org/wiki/List_of_dialling_codes_in_Italy
https://de.wikipedia.org/wiki/Telefonvorwahl_(Italien)