Facts about Britain's record-breaking Queen Elizabeth II

On Thursday, Queen Elizabeth II became first British monarch to reach the age of 90. It's just one of many milestones the queen has marked in her nine decades. Here's a look at some other numbers regarding Britain's queen:

— Elizabeth has reigned for 64 years and 75 days. On September 9, 2015, she became Britain's longest-reigning monarch, passing her great-great-grandmother Queen Victoria.

— She is the world's oldest monarch since the death of Saudi Arabia's King Abdullah last year.

— She has had 12 British prime ministers serve during her reign, from Winston Churchill to David Cameron.

— She has met 12 U.S. presidents, from Herbert Hoover (after he had left office) to Barack Obama — more than a quarter of all the U.S. presidents since Independence. The only president during her reign that she did not meet was Lyndon B. Johnson.

— She has traveled more than 1 million miles (1.6 million kilometers) on official trips, visiting 106 of the 193 current official members of the United Nations.

— She has visited Canada 22 times — the largest number of trips to any nation.

— She has four children, eight grandchildren and five great-grandchildren.

— She has cut back on her official duties in the last few years, but Elizabeth still conducted 177 official engagements in the last year.