Speaking to Gyles Brandreth in an article for The Daily Telegraph marking the Queen Mother's centenary in 2000, the Queen's husband said he had “no desire whatsoever” to live to 100.
He added: “I can’t imagine anything worse."
“Bits of me are falling off already.”
The Duke's milestone occasion was marked with a tweet from the Royal Family's official Twitter account, while the British Army fired a gun salute in his honour.
The Prince of Wales took to his official Clarence House Instagram account to show his dear old dad some birthday love with a throwback photo from 68 years ago.
"Happy 98th Birthday to HRH The Duke of Edinburgh. 🎉#HappyBirthdayHRH
"A two-year-old Prince Charles holds The Duke’s hand after greeting his father following his return home from a trip to Malta in 1951."
Philip's grandson Prince Harry also paid tribute via the Sussex Royal Instagram page he shares with wife Meghan Markle, while Prince William and Kate Middleton sent congratulations from their Kensington Palace profile.
Princess Eugenie got in on the action by sharing some adorable photos of herself and "grandpa", along with the touching message: "Happy Birthday to HRH The Duke of Edinburgh. I found a couple of classic photographs of Grandpa and I on Christmas Day and Trooping the Colour a few years ago now.."
Despite retiring from official royal duties two years ago, Prince Philip joined senior members of the royal family to celebrate Queen Elizabeth II's official birthday at the annual Trooping the Colour parade in London on Saturday.
But while the 98-year-old put on a united front with the Queen on the balcony of Buckingham Palace, shocking reports have emerged claiming the reigning royals are living "miles apart" and barely see each other.
Since his retirement in 2017, the Duke of Edinburgh has split his time between Wood Farm on the Sandringham Estate and Windsor Castle.
Royal Central editor Charlie Proctor told the Daily Star that the Greek-born Prince hardly spends any time at Buckingham Palace.
"It is in the middle of noisy central London, and perhaps doesn't offer the same peaceful tranquility as Windsor Castle of Sandringham House.
"As our 93-year-old Queen is still working, this is where she will spend the majority of her time in her workplace," he said.
Earlier this month, Philip skipped events for President Donald Trump's state visit to Britain.
In January, the outspoken and fiercely independent Prince sparked controversy when he caused a car crash outside the Queen's Sandringham Estate in Norfolk that left two women injured, ABC News reports.
Buckingham Palace issued a statement less than a month later confirming that "after careful consideration" the Queen's husband "has taken the decision to voluntarily surrender his driving licence".
This article originally appeared in New Idea.