Prince Charles hummed a few bars of The Beatles' When I'm Sixty Four at his birthday party at Government House in Wellington today.
Governor-General Sir Jerry Mateparae, whose birthday is also today, said hosting the prince on his birthday was the "icing on the cake" of the royal visit.
The idea to invite 64 Kiwis who shared the same birthday turned out to be an inspiration, he said, though he quipped that quite a few people tried to get on the guest list even if their birthday was on the wrong day.
"There was one person tried it on and their birthday was in March."
The success of the party spoke volumes about the genuine warmth New Zealanders had for the royal family, Sir Jerry said.
The prince was treated to a Maori rendition of Happy Birthday, followed by the English version. He then cut the cake while the band played When I'm Sixty-Four.
The cake was made up of 64 smaller cakes to create one large grid cake.
Images represented on the cake include a silver fern, jandals, hokey pokey ice cream and a tomato squeeze bottle.
Each of the invited guests will go home with one of the cakes, with the Prince getting his own slice.
Green lip mussel fritters, whitebait omelettes and kiwifruit pavlova were on the menu.
Today is also the birthday of Prime Minister John Key's wife Bronagh Key, who was at the party with her husband.
The 64 selected guests came from throughout the country - and one guest even travelled from San Diego.
Lenny Cheah said it was worth every penny of the ‘‘couple of thousand’’ dollars he spent flying to Wellington.
‘‘I wouldn’t have missed this for the world. It was the coolest thing,’’ he said after shaking hands with Prince Charles.
‘‘I didn’t know what to think when I found out I was coming here. It was like winning the lottery.’’
Mr Cheah, who turns 20 today, is a New Zealand citizen courtesy of his mother who is from Lower Hutt.
He said he was incredibly impressed by Charles and Camilla, who were very ‘‘well presented and put together.’’
Napier teenager Charlie Chittenden said he had planned to have a massive pool party with ‘‘plenty of Double Brown and Tui’’ on his 18th birthday.
But he was happy to swap a few beers with his mates for a glass of champagne with Prince Charles yesterday, after his mother put his name forward to be on the guest list.
‘‘It was really cool. The prince was a really nice guy — a bit posh for me though.’’
‘‘I told him I’d be out having a few pints later on if he wanted to join. He laughed and said ‘‘um, maybe’.’’
Charlie said he and his mother arrived from Hawke’s Bay this morning to find they had left his suit at home, resulting in an 11th-hour dash for some new threads.
‘‘It all worked out in the end though.’’
Aucklander Val Baker said she got to meet Prince Charles for the second time at his birthday party after shaking hands with him earlier in the day at his waterfront walkabout.
‘‘He didn’t recognise me though, unfortunately.’’
When Ms Baker told the prince she had travelled all the way from Auckland to be at his party, he laughed and said ‘sorry you had to come so far’,’’ she said.
‘‘Our talk was all over very quickly, but he was a lovely man.’’
Ms Baker said the experience of meeting Prince Charles and sharing in his birthday celebrations was something she would cherish forever.
Aucklander Stan Winkley, who turns 85 today, said Prince Charles got a laugh out of the fact that he was a vibrant 21 when the prince was born.
‘‘He said ‘you’re holding your age well’ or something like that,’’ Mr Winkley said.
The oldest guest was Mary Crosby, who turns 101 today.
FUTURE KING MEETS MOVIE KING
This afternoon the future king of the Commonwealth met the king of cinema at Weta Workshop.
About 200 people - many of them school children - stood outside the Miramar buildings hoping to catch a glimpse of Prince Charles as he met Sir Peter Jackson and Sir Richard Taylor.
The prince got a sneak peek behind the scenes of The Hobbit and watched actor Peter Hambleton, who plays Gloin, one of 13 dwarves in the yet-to-be released movie, get his makeup done.
When he walked into the makeup room he couldn't have uttered a more princely phrase when he said: "Oh my goodness gracious me".
He apologised to Hambleton for his having to go through the prosthetic process on his account.
When Prince Charles realised how much work went into the prosthetics, he said to Hambleton: "You are quite a way under all of this".
"Yes, I'm actually good looking," Hambleton replied.
Hambleton was excited about meeting Prince Charles.
"It's huge, it's a great thrill. I haven't had a chance to meet any of the royal family before so it's really exciting."
He said he hoped to meet some more royals at The Hobbit's London premiere, when guests will include Prince William and his wife, the Duchess of Cambridge.
Make up artist Sean Foot seemed nervous before meeting the prince.
"It doesn't happen every day, it's once in a life time. It's one of the benefits of working here."
Meanwhile, Prince Charles' wife Camilla, Duchess of Cornwall, had her first Kiwi high-five and an afternoon tea at Government House this afternoon.
The duchess had tea and sandwiches with about 25 female community leaders. Among those at the function was Endometriosis New Zealand chief executive Deborah Bush.
She said her sons had asked her to greet Camilla with a traditional Kiwi high-five, to which duchess obliged.
"We had a bit of giggle about it. She told me I could go home and tell the boys that the high-five had been delivered."
Thousands sang Happy Birthday to Prince Charles as he strolled with his wife on Wellington's waterfront earlier today - and a marriage proposal was also thrown in.
Throngs of people followed the couple from Te Papa to the TSB Bank Arena, with several renditions of Happy Birthday breaking out along the way. Throughout the excitable crowd, there were banners proclaiming love for the royals and one reading ''Marry me Charles''.
Wainuiomata resident Donny Shermond brought his two-year-old chihuahua Amigo along to meet the royals.
Shermond had met the royals before but said it was still thrilling.
His parents were from the Seychelles, where Prince William and Kate Middleton had their honeymoon.
''It was great to meet them. She was asking his (Amigo's) name and she has got a little chihuahua at home.''
Shermond, who is originally from Kenya, said he greeted the Prince in Swahili and he responded in kind.
Five-year-old Karori resident Jack Edmonds caught the Prince's attention with a sign announcing they shared the same birthday.
The couple were accompanied on their waterfront walk by Wellington Mayor Celia Wade-Brown.
Catherine Cacy of Wellington was the first person Prince Charles spoke to.
''I called out Happy Birthday and then he came straight over. He said, 'how did you know'?''
Robyn Ceverinsen of Paraparaumu was also lucky to get a moment with the prince. During their brief encounter she told him she was also born in 1948 and he replied that that was a good vintage.
Charles and Camilla are on the final leg of the Diamond Jubilee Tour.