Following the third, fourth, or fifth digit, every number up through 15 is the account number while that final number, 16, is the check digit. All Discover cards start with the number six and are 16 digits in length, while petroleum cards start with the number seven and airline cards start with the number one.
Vatican City. Vatican City â 0.2 square miles â The worldâs smallest state, the Vatican has a population of 770, none of whom are permanent residents. The tiny country which surrounds St. Peterâs Basilica is the spiritual center for the worldâs Roman Catholics (over 1 billion strong).
Comprising a territory spanning roughly 90,000 square kilometres (35,000 sq mi), the Maldives is one of the world's most geographically dispersed countries, as well as the smallest Asian country by both land area and population, with a little over 393,500 inhabitants.