Country code +378 (dialed as 00 378 from many places) is the Most Serene Republic of San Marino, a tiny republic completely surrounded by Italy.
Note that all landline telephone numbers in San Marino begin with +378 0549, followed by 6 further digits. Calls to and from Italy can be dialed with just the 10-digit national number. As with Italy, you do not drop the leading 0 of the national number in international format.
(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.)
Leichtenstein is telephone country code +423.
The Republic of San Marino, a European "micro-state" completely surrounded by Italy, is country code +378.All telephone numbers in San Marino begin with +378 0549, followed by 6 more digits, and you must include the 0 in 0549. Within Italy, you can dial just the 10-digit number beginning with 0549 to reach a number in San Marino.
The country code and area code of Bartin, Turkey is 90, (0)378.
where is telephone country code 1816
That is not a country code.
The country code and area code of Kaifeng- HEN, China is 86, (0)378.
The country code and area code of Tepatitlan- Jal., Mexico is 52, (01)378.
There is no 909 country code.
There is no telephone country code +897, nor +89, nor any other country code beginning with +89. There are no valid telephone numbers beginning with +89.
The country code and area code of San Marino, San Marino is 378, 0.
Gibraltar is country code +350.
Moldova is country code +373.