Area Code +84-4-(20000000...29999999) located in Ha Noi, more detail is as below. Place International Dialing Code : 84 International Prefix : 00 National Prefix : 0 National Destination Code : 4 Subscriber Number From : 20000000 Subscriber Number To : 29999999 National Destination Code Length : 1 Uses National Destination Code : Yes National Significant Number Length : 9 Number Type : G (Geographic Land Line, Fixed Line) Carrier Name : Viettel Click here to buy Vietnam Area Code Database Other Information Language Code : vi (Vietnamese) Country Number : 704 (Vietnam) Country Code : VN (Vietnam) City : Ha Noi Timezone : Asia/Ho_Chi_Minh Coordinated Universal Time : +07:00 Daylight Saving Time : No National Significant Number Minimum Length : 9 Latitude : 21.0300 Longitude : 105.8500 ‹ previous : +84-39-(6000000...6999999) next › : +84-4-(30000000...39999999) Dialling Instructions For trunk calls: 0 4 20000000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 00 84 4 20000000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 20000000 ~ 29999999 (Count: 10,000,000) Example: +84-4-20000000 / 0084-4-20000000 (04-20000000 / 0-4-20000000) +84-4-20000001 / 0084-4-20000001 (04-20000001 / 0-4-20000001) +84-4-20000002 / 0084-4-20000002 (04-20000002 / 0-4-20000002) +84-4-20000003 / 0084-4-20000003 (04-20000003 / 0-4-20000003) +84-4-20000004 / 0084-4-20000004 (04-20000004 / 0-4-20000004) ...+84-4-xxxxxxxx / 0084-4-xxxxxxxx (04-xxxxxxxx / 0-4-xxxxxxxx) ...+84-4-29999995 / 0084-4-29999995 (04-29999995 / 0-4-29999995) +84-4-29999996 / 0084-4-29999996 (04-29999996 / 0-4-29999996) +84-4-29999997 / 0084-4-29999997 (04-29999997 / 0-4-29999997) +84-4-29999998 / 0084-4-29999998 (04-29999998 / 0-4-29999998) +84-4-29999999 / 0084-4-29999999 (04-29999999 / 0-4-29999999)