For those of us who fetishize urban factoids, Mumbai is a goldmine of superlatives: it's one of the densest cities in the world; it's home to both Asia's largest slum and the world's largest and most expensive single-family home; and so on. Like New York, Shanghai, or Tokyo, Mumbai is one of those megacities perpetually at the forefront of the media's collective mind, and these facts have been repeated over and over until they have come to shape many people's superficial understanding of Mumbai.

But there is a lot more to Mumbai than density, Dharavi, and Antilla. So, lest you be caught in yet another conversation about the size and stature of Dharavi's (albeit admittedly impressive) recycling industry, I offer you a BMW Guggenheim Lab guide to 10 enlightening and fun facts about Mumbai that you might not have encountered before.

Source: flickr.com/photos/friarsbalsam

1. Mumbai has just 1.1 square meters of open space per person

Or less, depending on who you ask. Either way, that's less per person than in New York, Hong Kong, Shanghai, Mexico City and, yes, even Tokyo, making Mumbai not only one of the densest, but also the most cramped city in the world. (No, they don't necessarily mean the same thing).

2. Mumbai's mayor has hardly any power

One of the most important factors in how a city develops is who calls the shots. In Mumbai, the main power broker is not the mayor, voted in locally by citizens, but rather the Chief Minister of Maharashtra (the large state in which Mumbai is situated). Many believe that putting power in the hands of an official responsible for representing the interests of Mumbaikers only—someone who is held accountable to them during city elections—would gain Mumbai a greater degree of autonomy from the state government, and solve city problems more efficiently.

3. Mumbai has a toilet deficit

That's right—a deficit of 64,157 seats, to be exact, according to the most recent Human Development Report produced by the Municipal Corporation of Greater Mumbai and published by Oxford University Press. Realistically, the number is probably far greater than that, and many toilet blocks that do exist are in extremely poor condition. This is a bigger deal than it might sound. The vast majority of Mumbai's slum dwellers (over half the city's population) depend on public toilet blocks for their day-to-day needs. Lack of sufficient facilities leads many to urinate and defecate in the open, producing not only humiliating situations, especially for women, but unsanitary conditions that create breeding grounds for disease.

4. Mumbai has 149 kilometers of coastline

It's true—and many of those miles are currently much abused: clogged with garbage, stinking with water pollution, and generally abandoned by maintenance authorities. But with its oceanfront beaches, leafy mangroves, wetlands, mudflats, stunning carbon black rock outcrops, rivers and creeks, Mumbai's immense shoreline holds the potential for a lot of public space and ecological restoration. With a little political will, that is.

5. A good Mumbai slum house costs $5,600 to build

At least. And that's up in the northern 'burbs. If you want to buy into the realm of prime real estate in central locations like Dharavi, a house could run you more than a decent-sized house in Detroit, or enough to rent Leonardo DiCaprio's house for a month. Personally, I might take the place in Dharavi.

6. The number of people per square meter in a Mumbai commuter train at peak hour is so high, it has its own term

Yep: it's called a "super-dense crushload." I'm not making this up. Fourteen to 16 people per square meter, or 550 people in a train compartment designed to carry 200, to be exact. And what's more, unlike most other units of measurement, the super-dense crushload has actually changed over time. Fifteen years ago the term described a density of only 10-12 people per square meter. So Mumbaikers have either become more tolerant, thinner, or crankier on their daily commute. I have a sneaking suspicion it's the latter. Haven't experienced a super-dense crushload yourself? Give it a try: grab 15 friends and try to fit all of 15 inside a phone booth. You'll see why it's worthy of its own unit of measurement.

Source: BMW Guggenheim Lab

7. Public displays of affection are hot (and heavy) politics in Mumbai

Of all Indian cities, Mumbai is the one for getting hot and heavy in public. Want to see it for yourself? Take a walk to Bandra Bandstand or Carter Road—two public promenades known as Lovers' Point—and witness couples publicly smooching and "canoodling," as it's called in Mumbai, in a way otherwise entirely taboo in Indian culture. Some say Bollywood's depictions of the city have led to a more open mindset around PDA. Others chalk it up to Mumbai's cosmopolitism and heavy Western influence. But if you're thinking of engaging in any public heavy petting yourself, do so with caution: the Mumbai police are known for "moral policing," so a too-affectionate hug could cost you up to 1200 rupees (30 dollars) in fines. In a city where nearly 10 percent of the population earns 20 rupees (50 cents) per day, most without a place to call home, many simply can't afford to cuddle.

8. Mumbai is the seasonal home to a flamboyance of migrating flamingos

I'm not sure what is more fun: the existence of flamingos in Mumbai, or the fact that, just as a group of fish is called a school, a group of these pink birds is called a flamboyance. Either way, the seasonal Mumbai flamingos have been one of the city's secret gems since they magically began appearing in the 1990s on the Sewri-Mahul mudflats on the island city's eastern waterfront. Urban birders better be quick, though: waterfront development is coming soon and a new train line is set to barrel right through the habitat. Flamingo season runs through Mumbai's winter—roughly, October to March.

9. FSR 1 in Mumbai is not the same as FSR 1 in Manhattan

Or most other places, for that matter. At least not when it comes to the population density associated with it. First off, in simple terms, FSR or Floor Space Ratio (also known as FAR, Floor Area Ratio, and as FSI in India—Floor Space Index) describes the ratio of a building's floor area to that of the piece of land it is built on. So an FSR of 1 would allow a building that takes up the entire lot it is on to only be built one story tall. An FSR of 2 would allow it to be two stories. A building only taking up half that lot, however, could be two stories tall with FSR 1, and four with FSR 2. And so on and so forth. (Good examples can be found here if you need more explanation.) There is ongoing debate about Mumbai's FSR and whether or not it is too low. Many argue that raising Mumbai's FSR would help combat the city's out-of-control real estate prices and housing crisis by enabling developers to build higher condo buildings and increase housing stock. These higher FSR advocates often cite the fact that Mumbai's FSR, which currently sits at around 1.33 should rather reflect that of Manhattan, which can range to 10 or higher. But others, especially renowned Mumbai architect and city planner Shirish Patel, caution against this simplistic thinking, citing the fact that a far greater density of people, sometimes several families at a time, cram into each apartment unit in Mumbai—far more than would do so in Manhattan. That means that the number of people that would be added into a neighborhood in Manhattan with an FSR increase might be tenfold that number for the same increase in Mumbai. Anyone who has been to Mumbai knows that the city's streets, sidewalks, and transportation system are already crushingly crowded and overcapacity. An FSR increase could tip this over the edge—if it hasn't indeed been tipped over already—further lowering the standard of living.

10. Ninety percent of Mumbai's workers are informal

If you want big numbers, forget Mumbai's informal housing statistics, and look to the city's economy, where a whopping estimated 90 percent of employment occurs in the informal sector. Whether its people rag-picking on the streets, hawking fruit and veggies, sweeping, slinging vada pav, or, yes, recycling in Dharavi, the size of the informal sector and percentage of the city's workers it employs has skyrocketed since the downfall of the city's industrial and manufacturing sectors in the 1980s and '90s. That means almost an entire generation of workers without benefits, retirement plans, or job security… and a city budget bearing whole lot of uncollected taxes.

Anyone have any more things urbanists should know about Mumbai? How about other cities?