An unforgettable dress has been sold for an unbelievable sum.

The dress actress Marilyn Monroe wore when she sang an incredibly sexy rendition of “Happy Birthday” for President John F. Kennedy in 1962 has been auctioned off for $4.8 million.

Ripley’s Believe It Or Not! purchased the dress on Thursday night at a Julien’s Auctions event in Los Angeles.

The company plans to first put it on display at the company’s Odditorium museum in Hollywood as the centerpiece of a Marilyn Monroe collection before sending it to some of the other Odditoriums around the world.

Getty Images The dress that Marilyn Monroe wore when she sang "Happy Birthday" to President John F. Kennedy has been auctioned off for $4.8 million. The dress was purchased by Ripleys Believe It Or Not!

Edward Meyer, Ripley’s vice president of exhibits and archives, lauded the dress’ historical importance.

“This is the most famous item of clothing in 20th century culture,” he stated in a release. “It has the significance of Marilyn, of Hollywood, of JFK, of American politics. Any museum in the world would love to have it on display, and now it belongs to Ripley’s Believe It or Not!”

Ripleyscom Ripley's Edward Meyer poses next to the dress Marilyn Monroe wore when she sang at President John F. Kennedy's birthday.

Monroe wore the dress on May 19, 1962, while performing in front of 15,000 people at JFK’s 45th birthday party.

According to a Julien’s Auction release, the dress is studded with more than 2,500 hand-stitched crystals and was so tight that the actress ― who wore nothing underneath ― had to be sewn into it.

The fit of the dress may explain Monroe’s breathy delivery, which fed rumors that she and “Mister President” were having an affair.

Kennedy’s response to Monroe’s performance is almost as famous. He told the crowd: “I can now retire from politics after having had ‘Happy Birthday’ sung to me in such a sweet, wholesome way.”

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