What is the name of the first balloon to fly nonstop around the world?

Breitling Orbiter 3 was the first balloon to fly nonstop around the world.

Bertrand Piccard and Brian Jones completed the first successful nonstop circumnavigation by balloon in Breitling Orbiter 3 in 1999. They launched from Château-d’Oex, Switzerland, on 1 March and landed in Egypt on 21 March after a flight lasting 19 days, 21 hours, and 47 minutes.

The craft was a Rozière balloon, a hybrid design that combines helium lift with a hot-air system. This arrangement allowed the pilots to manage altitude over a much longer journey than a conventional hot-air balloon could usually sustain.

Breitling Orbiter 3 is sometimes confused with Virgin Atlantic Flyer, which set a major Pacific-crossing record in 1991. The earlier Atlantic and Pacific crossings were important steps, but Orbiter 3 was the craft that completed the first nonstop balloon circumnavigation.