Justin Bieber headed to a Caribbean island for an exclusive party in Antigua attended by the island's Prime Minister.

The 22-year-old dreadlocked singer threw a party on Antigua's Jumby Bay Island last weekend (16-17Apr) to celebrate his chart success, where he was joined by friends and even Prime Minister Gaston Browne, 49, popped by.

The What Do You Mean? singer, and his pals partied on board a tanker-turned-party boat that comes complete with inflatable slides so guests can dive straight into the sea.

A source told British newspaper The Sun: "Justin's had a phenomenal year and wanted to have a blowout to celebrate. They loved it."

The moored boat also features a massive trampoline as part of its own water park, bar and sun-loungers.

When he wasn't at sea, Justin reportedly stayed in a house owned by TV star Dr. Oz and only ventured to mainland Antigua to enjoy dinner at an Italian restaurant by the harbour.

Justin's hit song Love Yourself has now made chart history after spending its first 22 weeks on the Billboard Hot 100 Top 10. This smashes a record set by the artist earlier this year, when his comeback single Sorry debuted in the Top 10 and spent 21 consecutive weeks there.

Meanwhile a new study has found that people between the ages of 18 and 25 are more likely to recognise Justin's lyrics than words crafted by William Shakespeare, who celebrates his 400 year anniversary this week.

The survey, commissioned by Deezer, found that 43 per cent of young people could identify Bieber lyrics while only 38 per cent recognised the work of England's famous playwright.

Over half knew the lines "Girlfriend, girlfriend, you could be my girlfriend" and "Is it too late now to say sorry?" were from Bieber songs, while only a third knew "To be or not to be" was a Shakespearean line.