Where is area code 729?

Answer 1

There is no area code +1 729 in North America (USA, Canada, etc.).

There are no valid UK numbers beginning with +44 72.

There may be an area code 729 in some other country.

Country code +7 is Russia and Kazakhstan, but there are no numbers beginning with +7 2.

(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.)

Answer 2

North American area code +1 729 is unused. It is not a valid area code.

Answer 3

Denver is one of them