Lady Gaga's "Born This Way" has debuted at the top of the chart to become the one-thousandth #1 in the 52-year history of the Hot 100's.  In addition, "Born This Way" sold a whopping 448 thousand copies in its opening week according to Nielsen Soundscan -- the biggest debut sales week for a song by a female artist.  It breaks the record Britney Spears set a month ago with "Hold It Against Me," which sold 411,000 copies.

"Born This Way" has now set the record for the third-largest digital debut in history, right behind "Right Round" by Flo Rida and The Black Eyed Peas' "Boom Boom Pow," which sold 636 thousand and 465 thousand copies respectively.  It's just the 19th song in 52 years to debut at #1 -- and it's Gaga's third #1 overall on this chart.

Lady Gaga told Billboard that her milestone is

"a tremendous honor,"and added, "To be the 1000th no. 1 on Billboard...I would be silly not to say this is the greatest honor of my career."

She also said she has been

"so humbled and so honored and overwhelmed by the reception to 'Born This Way,'" and stated, "I couldn't be more blessed to have the fans that I have."

The Billboard Hot 100 started on August 4th, 1958, with the #1 hit "Poor Little Fool" by Ricky Nelson.  The 500th #1 was "Keep on Loving You" by REO Speedwagon, in 1981.