020 is the telephone dialling code for all of London.
Area code 020 is London, including the old "inner London" and "outer London" areas.
This is a code for an area of London but has been written incorrectly. It should read 020 3634
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.
dial 011 then the number. 011 is the number for international calling.
The international dialling code for mainline China is +86
The international dialling code for the UK is +44. You need to drop the leading zero from a UK number when dialling from abroad, so a London number of 020 111 2222 would be +44 20 111 2222.
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
The international dialling code is +44 (or 0044). The area code for London is 020, but you drop the leading zero if phoning from abroad. For example, to phone a London number 020 111 2222 from abroad, you would call; 0044 20 111 2222.