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).
It may be difficult to imagine, but there is a country in the world smaller than New York Cityâs Central Park and one with a population smaller than a typical high-school class. Based on landmass, Vatican City is the smallest country in the world, measuring just 0.2 square miles, almost 120 times smaller than the island of Manhattan. Situated on the western bank of the Tiber River, Vatican Cityâs 2-mile border is landlocked by Italy.