Where is telephone country code 1 284?

Telephone country code +1 is North America, including the USA and Canada, plus some assorted islands, mostly in the Caribbean.

Telephone area code +1 284 is specifically the British Virgin Islands.

Note that to call the British Virgin Islands from the USA or Canada, you dial "one-plus," 1-284-xxx-xxxx, the same way you would dial a domestic long distance call; however, international calling charges will apply.

(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 Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)