It may well be his height.

The 1.86m-tall funnyman behind the viral hit PPAP (Pen-Pineapple-Apple-Pen) arrived in Singapore on Sunday for a 20-minute appearance at the end of Anime Festival Asia Singapore.

Most people do not realize how tall he is, he admits. "Usually you see me on a small screen, on YouTube," he says at a pre-performance media conference.

His height matches his towering success in the world of viral videos - since PPAP was uploaded in August, the 45-second song has racked up 91 million views on YouTube, has been namechecked by Canadian pop star Justin Bieber and even scored a Guinness World Record for being the shortest song to chart on the US Billboard Hot 100 charts.

There are plans for him to release an album. One possible track on the album is his most recent song, the 54-second Neo Sunglasses, which bears his usual offbeat dance moves and lyrics, which are mostly the words "dazzling" and "dark".

(Read also: Pen-Pineapple-Apple-Pen sets world record)

A pop-up Pen Pineapple Apple Pen cafe opened in Tokyo earlier this month, serving food comprising apples, pineapples and even chocolate sticks or "pens".

While some might dismiss his song and antics as silly (PPAP has 25 words and most of them are "apple" "pen" and "pineapple"), Piko-Taro says his music carries big themes of world peace and love.

"For me, a song is something that can make people smile. The lyrics don't have to have a great meaning, but if it can make people laugh and dance, then that gives it meaning," he says, speaking through an interpreter.

Referring to the many people across the world who have made their own versions of PPAP - from Bollywood-style to beatboxing and ballads - he says: "I think why it went so viral is because so many people have covered the song. It becomes everyone's song."

Japanese television channel Wakuwaku Japan brought him to Singapore for a music program that will air on Dec 30.

Piko-Taro, the alter-ego of 53-year-old Japanese comedian Kazuhiko Kosaka, is charming and his energy, infectious.

(Read also: Piko-Taro releases extended version of viral hit ‘Pen-Pineapple-Apple-Pen’)

When he notices this reporter's carefully chosen leopard print dress, he says with wide eyes and in limited English: "Oh nice, like Piko-Taro!"

Asked to reveal something people might not know about him, he raises his right pant leg: "It's the biggest secret I've never told any media - my shoe size is 29cm."

And touching his right forearm, he adds: "And another secret, I have very nice skin. Baby skin."

He performed PPAP three times at the Anime Festival Asia on Sunday.

If anyone was sick of the crazily catchy earworm, it did not show - the 2,500-strong crowd at Suntec Singapore Convention & Exhibition Centre sang, danced and laughed along with Piko-Taro as he performed his hit song.

Besides the original version, he also performed the longer version of PPAP - a 2-minute 40-second version with more lyrics and an R&B-style music segment designed to showcase his offbeat dancing.

With tongue firmly in cheek, he declares at the end: "The song is so short because I get tired. I'm still catching my breath."