County Mayo, Ireland, has several different area codes, including at least 094, 096, 097, and 098. Calling from the UK, including Northern Ireland, you must dial the number in full international format: replace the leading 0 of the Irish area code with country code +353. From a mobile, dial +353 9x; from a landline, dial 00 353 9x, followed by the local number (mostly 5 digits).
(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)
Luton's dialling code is 01582.
567218 is not a dialling code from the UK, which all start with zero. The dialling code for Glasgow, Scotland is 0141.
The international dialling code for mainline China is +86
The code for Belfast and all other Northern Ireland numbers is 028. As Northern Ireland is in the UK, no other prefix is required when dialling from England.
0141 is Glasgow's dialling code. 952 is not a dialling code in any part of the UK.
The dialling code from UK to Australia is 00 61.
+51
001
Portugal
The international dialling code for Germany is 49 So, if phoning from the UK, dial 0049
Dialling code for Switzerland is +41
No. The International Dialling Code for the UK is 0044.