On the same day "Barbie" passed its billion-dollar box office milestone, the other half of the viral "Barbenheimer" phenomenon blew past the half-billion-dollar mark.

Since its release three weeks ago, Christopher Nolan's "Oppenheimer" has made $552.9 million worldwide, according to official estimates from Universal Pictures.

It is now the highest grossing R-rated movie of 2023, and "marks the fastest a Universal R-rated film has hit the $200 million threshold domestically," the studio said in a news release Sunday. It's also the highest grossing movie set during World War II, according to Universal.

In its third weekend, "Oppenheimer" has had incredible stamina as the No. 3 movie in both domestic and international box offices.

Nolan's blockbuster has had "an astounding theatrical run made all the more impressive by the R-rating, running time and subject matter which, in the hands of a lesser filmmaker and absent a spectacular marketing and release strategy, would have likely wound up as a mere footnote when referencing the performance of historical dramas at the box office," said Paul Dergarabedian, senior media analyst at Comscore.

The box office numbers are impressive for a three-hour biography about J. Robert Oppenheimer, the Manhattan Project physicist. The movie is one of only four biopics to earn more than half a billion dollars globally, alongside "Bohemian Rhapsody," "Passion of the Christ," and "American Sniper."

"'Oppenheimer'... (has) become one of the most revered, talked about and successful summer movies ever to be released by a major studio," said Dergarabedian, adding the movie "demonstrates the power of great filmmaking and of course a bit of unforeseeable 'Barbenheimer' magic."

"Oppenheimer" and "Barbie" had a symbiotic relationship in the lead-up to their shared debut on July 21, perhaps helped by their very different styles and tones.