All of New Delhi is in area code 011, which is +91 11 from outside India.
(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, and many other countries use different prefixes.)
505 is the area code for Zuni, New Mexico.
The country code and area code of Belep, New Caledonia is 687, 42.
The country code and area code of Boulouparis, New Caledonia is 687, 35.
The country code and area code of Lifou, New Caledonia is 687, 45.
Newark, NJ, is in area code 973, with overlay code 862.
The country code and area code of Antarctica, New Zealand is 64, (0)2.
The country code and area code of New Bussa, Nigeria is 234, (0)33.
The country code and area code of New Halfa, Sudan is 249, (0)421.
In 2001, area code 973 in northern New Jersey was overlaid with area code 862. The overlay code was originally announced to be 356, but was changed.
The country code and area code of Goroka, Papua New Guinea is 675, 70.
New Brighton, MN, is in area code 651. New Brighton, PA, is in area codes 724 and 878 (overlay).
Leonardo, NJ, is in area code 732, with overlay area code 848.