It's about 150 times the number of Countries in the European Union.
In other words, the count of Countries in the European Union is 0.0071 times 3,900.(a.k.a. EU) (2016 figures)
It's about one-one-hundred-fiftieth the number of Words in War and Peace.
In other words, 3,900 is 0.00664071 times the count of Words in War and Peace, and the count of Words in War and Peace is 150.586 times that amount.(1869) (1968 Ann Dunnigan translation, New American Library)
It's about 250 times the number of Living Kings and Queens.
In other words, the count of Living Kings and Queens is 0.0038 times 3,900.(2015 figures) (distinct Monarchs)
As of 2015, the world has fifteen Kings and Queens reigning over 45 countries. Of all these, Queen Elizabeth the II is the only reigning Queen; she has monarchical authority over the sixteen of the Commonwealth nations.
It's about 450 times the number of Symohonies Composed by Beethoven.
In other words, 3,900 is 433.333333333 times the count of Symohonies Composed by Beethoven, and the count of Symohonies Composed by Beethoven is 0.00230769230769 times that amount.(a.k.a. Ludwig van Beethoven)
It's about 800 times the number of Living U.S. Presidents.
In other words, the count of Living U.S. Presidents is 0.001 times 3,900.(a.k.a. Presidents of the United States; a.k.a. Presidents of the United States of America; a.k.a. POTUS), (2016 figures) (including current)
As of this writing, there are five living United States Presidents — President Carter, President Clinton, President Obama, and the two Presidents Bush. At no point in U.S. history have their been more than six (6) living presidents, this circumstance having occurred three times.
It's about one-one-thousandth the number of ATMs in the World.
In other words, the count of ATMs in the World is 1,000 times 3,900.(2015 figures) (approximate)
It's about 2,000 times the number of Escalators in the State of Wyoming.
In other words, the count of Escalators in the State of Wyoming is 0.0005 times 3,900.(2013 figures)
There are only two escalators in the State of Wyoming (although there are apparently plenty of elevators). It is speculated that the lack of escalators is due to the older age of the buildings and the abundance of cheap land resulting in single-story structures. At the time the last count of escalators was made, the state had a population of just 576,000 people.