LONDON, July 22 -- The world's biggest YouTuber is officially off the market.

MrBeast, whose real name is Jimmy Donaldson, has married longtime girlfriend Thea Booysen in an intimate week-long celebration on Sir Richard Branson's private Necker Island in the British Virgin Islands, People magazine revealed in an exclusive.

Despite being one of the internet's biggest stars, the 28-year-old kept the wedding deliberately low-key, inviting just 70 friends and family members. There were no livestreams or YouTube cameras - only a professional wedding photographer.

Guests spent several days kitesurfing, snorkelling and exploring the 74-acre island before the couple exchanged vows in a ceremony officiated by a family friend.

Booysen, a South ...