Normally, 'international format' means you need to prefix you domestic number with the symbol "+" and the relevant country code, as well as removing any digits that aren't dialled by international callers. In other words, you are including the additional information needed to call internationally in the number.
In the United Kingdom, the country code is "44". In addition, the initial zero of the domestic number is not dialled when calling internationally.
For example, 07234 567890 would become +44 7234 567890
In a similar way, the French number 07 2345 6789 would become +33 7 2345 6789 because the country code for France is 33 and, again, the first zero is not dialled when calling from outside the country.
The "+" symbol tells the caller to dial whatever code they need to begin a local call from their current location (this varies around the world).
An example of a valid mobile number for someone in the UK would be in the format +44 7xxx xxxxxx... Where +44 is the international access code for the UK, 7xxx would be the code for the mobile number (without the leading zero) and the remaining six digits identify a specific user.
All the international format involves is adding a country code in front of the other numbers. A number of businesses have their contact phone numbers in the international format
Replace the trunk prefix 0 of the Indian domestic number with country code +91, and use only blank spaces to separate groups of digits. For example, +91 9xxx 123123.
An example of a valid mobile phone number might be +1 417 555-0123, except with an actual mobile phone number instead of the fictitious 555-0123. An example in the UK would be +44 7700 900123, which is the (fictitious) UK mobile number 07700 900123 written in international format. A valid mobile phone number is a real phone number that actually connects to a working mobile phone.
That is a valid format for a UK mobile (cell) number. The 7 in the position that it is in identifies it as a mobile number. 00 is the international gateway code, 44 is the country code for UK. Short of dialling it there's no way to know whether it is actually an active number.
+44 770 is the beginning of a UK mobile phone number in international format. In domestic format, the same number would begin with 0770.(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.)
A UK telephone number beginning with 07531 (or +44 7531 in international format) is a mobile phone.(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.)
That's an Etisalat mobile number from the United Arab Emirates, country code +971. The correct international format is +971 56 xxx xxxxDo not use any punctuation at all, other than the plus symbol at the start. In particular, no periods, dots, dashes, parentheses, or brackets should be used.(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.)
There are no valid international numbers beginning with +7501 (Country code +7 is Russia and Kazakhstan, but numbers beginning +7 5 are unassigned.) In the UK, 07501, or in international format +44 7501, is a mobile code.
00 isn't part of the telephone number, it is a commonly used prefix for dialing international calls. However, many countries use different prefixes, so it is less confusing to quote the number in correct international format, beginning with the plus sign and the country code.Country code +241 is Gabon in Africa. However, there are no valid numbers beginning with +241 0. Mobile phone numbers in Gabon begin with 0 in domestic format, but you must drop the trunk prefix 0 when dialing in international format. Without the 0, you do not have enough digits for a valid telephone number. All numbers in Gabon have 8 digits after the country code. Note also that Gabon changed all telephone numbers in the country in 2012.(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.)
That is not a valid international telephone number.
This is a UK mobile (cell phone) number.
That's not a valid number.
That is not a valid telephone number either in North America or in international format. Unfortunately, it is very easy for a business switchboard to be "accidentally" programmed to send bogus Caller ID data.
There are no valid UK telephone numbers beginning with 0728 (or +44 728 in international format).