MONACO (AP) — Billionaire art collector David Nahmad can't fully recall why he bought “Nature Morte,” a charmingly simple oil on canvas that Pablo Picasso painted in 1921.

Given that Nahmad owns about 300 of the Spanish genius' works, his forgetfulness is perhaps understandable. With such a princely trove — Nahmad says his Picasso collection is the world's largest in private hands — details sometimes get lost.

“We bought so many Picassos now, I don’t remember the specific reason," Nahmad said in an exclusive and rare interview with The Associated Press in his luxury home in Monaco.

“It’s the smallest painting that I have."

Not for much longer.

A very lucky someone, somewhere, will soon be joining Nahmad in the privileged club of Picasso owners, when “Nature Morte” is raffled off for charity this month.

Tickets, sold online, are 100 euros ($113) each. The winner of a similar raffle in 2013 was a 25-year-old fire sprinkler worker from Pennsylvania.

Nahmad, one of the art world's most influential dealers, will receive 1 million euros ($1.1 million) for “Nature Morte" but says it is worth “at least two, three times” that.

“This raffle would not have succeeded if the name was not Picasso. I tried to propose other artists’ names. But it would not work, because they wanted a name that would appeal to everybody. It has to be Picasso. Picasso is the magic name," he told the AP.

Other paintings in Nahmad's vast collection of modern and impressionist art are more valuable and celebrated. Accumulated over decades, the stockpile is said by Forbes to be worth $3 billion. Nahmad himself won't say.

“I don’t think people care about the number of works, but about their quality,” he said.

But Nahmad says the prospect of parting with “Nature Morte” has made him more appreciative of the small still life, which is signed “Picasso" and shows a newspaper and a glass of absinthe on a wood table.

The artist was a new father, to Paulo, with his Russian first wife Olga Khokhlova and was months shy of his 40th birthday when he completed the painting in June 1921.

“I think this painting is extremely chic," Nahmad said. “And the fact that it is small, it makes it not pretentious. A small jewel.”

The raffle draw is being held in Paris on March 30. Organizers Péri Cochin, a television producer, and Arabelle Reille, an art historian, aim to sell 200,000 tickets, raising millions to provide water for villagers in Cameroon, Madagascar and Morocco.

They decided to pay Nahmad for the painting, rather than push for a free donation, because they hope to encourage other collectors or galleries to also part with Picasso works for future charity raffles.

“David first said, ‘I don’t think I have a painting for a million euros. I have really beautiful paintings that are worth much more than that. But you know what? Let's go together to my book, my collection book, and we'll try to find something together,'" Reille recalled.

“For a million euros, usually you can get a nice drawing, a water color, a beautiful print. But it's extremely rare to find a painting, and we did find this one in the end," she said.

Nahmad, 72, started dealing art with his brothers in the 1960s, paying as little as $5,000 for pieces by Picasso and building the hoard of works that made them into billionaires. Nahmad's sumptuous apartment in Monaco is in one of the principality's most sought-after addresses for the rich and famous, with spectacular Mediterranean vistas. Sculptures by Alberto Giacometti grace the home and works by French cubist painter Fernand Léger and other artists decorate Nahmad's walls.

He says his artworks are as dear to him as children and that parting with them is difficult. He recalled early purchases of works by René Magritte, the Belgian surrealist, Irish-born painter Francis Bacon and others when they could still be bought cheaply. Nahmad said his ambition “before I die” is to keep improving his already fabulous collection, describing it as "a living thing.”

“You learn every day,” he said. “A statement of a bank, it is so boring. Each time you buy a painting, you want to know more.”

Nahmad believes that Picasso, who died in 1973, would have liked the raffling of his work to the public.

"Picasso was very generous. He gave paintings to his driver, his tailor,” Nahmad said. “He wanted his art to be collected by all kinds of people, not only by the super-rich.”

His hope for “Nature Morte” is that the winner will be someone who appreciates it. If not, “I will be very unhappy" and “would like to buy it back," Nahmad said.

“There’s nothing worse than to own something without understanding that thing,” he said.

“It’s like people: If you don’t understand a person — whether it’s your wife, your girlfriend or whatever — you can never like them.”