To many revelers, the Fourth of July is an excuse to relax under the hot sun with cold beers while indulging in high-calorie foods, but the history of America’s Independence Day is richer than anything on their holiday bill of fare. Here are 15 fun facts about the U.S. birthday likely to surprise family and friends:

1. How many people signed the Declaration of Independence on the Fourth of July? Two.

2. Which day did most signers of the Declaration of Independence actually put their John Hancocks on the document? Aug. 2, 1776.

3. Which president was born on the Fourth of July? Calvin Coolidge, the 30th president, in 1872.

4. How did the Nathan’s Fourth of July Hot Dog Contest begin? Legend has it that four immigrants got into an argument over who was more patriotic. They decided to settle the disagreement by seeing who could eat the most wieners.

5. When did the Fourth of July become a paid federal holiday? 1938.

6. Is there something written on the back of the Declaration of Independence? Yes. Appearing upside down on the bottom of the document are the words, “Original Declaration of Independence dated 4th July 1776.” The memo may have been written as a label.

7. Did you know three of the first five U.S. presidents died on the Fourth of July? John Adams, Thomas Jefferson and James Monroe all died on Independence Day. Even weirder, Adams, the second president, and Jefferson, the third, died on the same day in 1826, the country’s 50th birthday.

8. Are there Fourth of July celebrations in other countries? Yes. They are featured in Denmark and Norway, as well as Britain, Portugal and Sweden. Danes and Norwegians celebrate the American Independence Day because so many thousands of their fellow citizens emigrated to the U.S. in the early 1900s. In the other European countries, American military bases host celebrations, which are supported by local businesses as a way to boost tourism.

9. Did you know John Adams would think the country is celebrating Independence Day on the wrong day? Adams foresaw that July 2, the day the Second Continental Congress voted to declare independence from Britain, would be the day on which Americans would celebrate their freedom. “The Second Day of July 1776, will be the most memorable Epocha, in the History of America,” Adams wrote.

10. When were fireworks first used to celebrate the Fourth of July? The initial fireworks were ignited in 1777 to commemorate the first anniversary of the American colonies’ Declaration of Independence.

11. Which newspaper first printed the Declaration of Independence? The Pennsylvania Evening Post.

12. Which country gained independence from the U.S. on the Fourth of July? The Philippines did so in 1946.

13. There was a baseball pitcher who threw a 4-0 no-hitter against the Boston Red Sox July 4, 1983: Who was it? The New York Yankees’ Dave Righetti authored this gem. It was the first no-hitter tossed at Yankee Stadium in 27 years.

14. Which president was the first to hold a Fourth of July celebration at the White House? Thomas Jefferson.

15. How many people lived in the American colonies when the Declaration of Independence was signed? 2.5 million.

88824090 Surprise family and friends on the Fourth of July by knowing these fun facts about America’s Independence Day. Photo: Getty Images

Follow me on Twitter @mariamzzarella