Friday marks Queen Elizabeth II's 91st birthday. The queen of England, whose full name is Elizabeth Alexandra Mary Windsor of York, was born April 21, 1926. She became monarch on Feb. 6, 1952, and is today the world's longest reigning living monarch.

"The Queen usually spends her actual birthday privately, but the occasion is marked publicly by gun salutes in central London at midday: a 41 gun salute in Hyde Park, a 21 gun salute in Windsor Great Park and a 62 gun salute at the Tower of London," the royal website states.

The queen remains in good health and continues to carry out her royal duties despite several rumors about her possible abdication after she fell ill following a bad cold last year, forcing her to skip important annual events.

Here are some facts and photos to celebrate the queen's birthday: 

1. Queen Elizabeth II has been the head monarch of the United Kingdom since 1952.

2. Twelve prime ministers have served under her.

3. She knows how to speak French and how to drive.

4. The queen does not have a passport — she can travel anywhere in the world without one.

Queen Elizabeth II Queen Elizabeth II, then Britain's Princess Elizabeth II, is pictured representing her father King George VI at Windsor Castle on May 26, 1951. Photo: Getty Images

5. The queen was 3-years-old when she first featured on the cover of TIME.

6. Her 1953 coronation was the first to be televised.

7. The queen's first tweet was in 2014. It read, "It is a pleasure to open the Information Age exhibition today at the @ScienceMuseum and I hope people will enjoy visiting. Elizabeth R."

8. Her nickname as a child was "Lilibet."

queen elizabeth Queen Elizabeth posed in 1953 at her coronation after being named queen in 1952. Photo: AFP/Getty Images

9. The queen holds a private meeting with the prime minister every week.

10. She loves eating mangoes.

11. The queen has a personal bagpipe player.

Queen Elizabeth at Westminster Queen Elizabeth waits before delivering her speech in the House of Lords, during the State Opening of Parliament at the Palace of Westminster in London May 8, 2013. Photo: Reuters/Toby Melville

12. She has about 30 godchildren, one of who is Charles Spencer, the brother of the late Princess Diana.

13. Former U.S. President Barack Obama had once gifted the queen an iPod.

President_Reagan_and_Queen_Elizabeth_II_1982 President of the United States Ronald Reagan and Queen Elizabeth II Horseback Riding at Windsor Castle, England in 1982. Reagan is riding Centennial and the Queen is on Burmese. Photo: Michael Evans