The home of India’s richest person has three helipads and a theater.

MUMBAI - The newest and most exclusive residential tower for this city's superrich is a cantilevered sheath of steel and glass soaring 27 floors. The parking garage fills six levels. Three helipads are on the roof. There are nine elevators, a spa, a 50-seat theater and a grand ballroom. Hundreds of servants and staff are expected to work inside. And now, finally, after several years of planning and construction, the residents are about to move in.

All five of them.

The tower, known as Antilia, is the new home of India's richest person, Mukesh Ambani, whose $27 billion fortune also ranks him among the richest people in the world. And even here in the country's financial capital, where residents bear daily witness to the stark extremes of Indian wealth and poverty, Mr. Ambani's building is so spectacularly excessive that the city's already elastic boundaries of excess and disparity are being stretched to new dimensions.

"One family is going to live in that?" said Prahlad Kakkar, an advertising filmmaker and prominent city resident. "Either it is a landmark, or a symbol, or it is Mammon." He added: "There is shock and awe �?both at the same time."

Mr. Ambani, his wife, Nita, and their three children are expected to move into the building after a housewarming party with 200 guests on November 28. Mr. Ambani has refused to comment about the project and required his designers, decorators and contractors to sign confidentiality agreements.

But some details have leaked out. Reports have estimated the total residential space at 37,000 square meters, though people close to the project say the real number is a humbler 5,500 square meters. Press accounts also have estimated the value of the building at $1 billion, a figure disputed by people familiar with the project.

Regardless, a gawking city has greeted the new tower with a mixture of moralizing and astonishment, envy and condemnation, sprinkled with Freudian analysis of the most basic question: Why did he do it?

"We are all sort of perplexed," said Alyque Padamsee, a long-time advertising executive and actor in the city. "I think people see it as a bit show-offy."

For decades, the Ambani family has been India's most famous corporate soap opera. The father, Dhirubhai Ambani, was a brazen, rags-to-riches tycoon who established Reliance Industries after rising out of the city's tenements. Today, Reliance is the world's biggest producer of polyester fibers and yarns and accounts for almost 15 percent of India's exports, according to the company's annual report.

The two sons, Mukesh and Anil, inherited and divided the empire and have spent years feuding, including a recent fight over natural gas rights that brought a reprimand from the prime minister before India's Supreme Court settled the case in Mukesh's favor.

The new tower is located on Altamount Road, the same leafy residential street in south Mumbai where the father bought his first home after moving out of the tenements. Later, he purchased a 14-story apartment building named Sea Wind, where Mukesh and Anil have lived with their families on different floors, even during their feud. Now Mukesh is moving into a tower that makes Sea Wind seem like a guest house.

"It's kind of returning with a vengeance to where they made it into the middle class and trumping everybody," said Hamish McDonald, who chronicled the family's history in his book, "Mahabharata in Polyester: The Making of the World's Richest Brothers and Their Feud." "He's sort of saying, ‘I'm rich and I don't care what you think,'�? he said.

Mumbai, once known as Bombay, is India's most cosmopolitan city, with a metropolitan area of roughly 20 million people. Migrants have poured into the city during the past decade, drawn by Mumbai's reputation as India's "city of dreams." But it is also infamous for its poor: a recent study found that roughly 62 percent of the population lived in slums, including one of Asia's biggest, Dharavi, which houses more than one million people.

Real estate prices are among the highest in the world, pushing many working-class residents into slums, even as developers have cleared land for a new generation of high-rises for the affluent.

High-rises are considered necessary, given the city's limited land, yet the rising towers have further insulated the rich from the metropolis below.

Along Altamount Road, the reaction to the new neighbor is mixed. Sushala Pawar struggled to comprehend the difference in Mr. Ambani's life and her own.

She cooks for a family in a nearby apartment, earning 4,000 rupees a month, or about $90. She sleeps on the floor of the hallway after the family has gone to bed.

"I'm a human being," she said. "And Mukesh Ambani is a human being. Sometimes I feel bad that I live on 4,000 rupees and Mukesh Ambani lives there."

But then, nodding toward the building, she said, "Maybe, I could get a job there."

The New York Times