On February 5, Super Bowl 51 will bring the country to a standstill. But lots of money will have already moved around. Watching huge men attack each other has been popular since Roman times, and gladiators in the Colosseum might have been seen by tens of thousands. Now more than 100 million will view their modern equivalents, and that generates big bucks. Super Bowl spending topped $15.5 billion last year, according to the National Retail Federation.

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It's a big deal for any city hosting the event — Houston in 2017. Janice Evans, the chief policy officer for Houston's mayor, said hosting the game will cost the city an estimated $5.5 million, primarily through increased need for police, fire and emergency personnel. The Houston Super Bowl Host Committee, a private nonprofit, will reimburse the city for the expense, though, and it's worth the trouble. She said the game is expected to bring at least $350 million to the local economy as visitors spend on hotels, entertainment, food and drink. "It's much more of an event than other games," said Kevin Cooper, a spokesman for the Host Committee. Besides local attendees and celebrants, 140,000 people are expected to descend on the city for Super Bowl 51. The venue for Super Bowl 51, NRG Stadium — named for utility company NRG Energy, which gained the rights through a 32-year, $300 million deal originally signed by Reliant Energy in 2002, the biggest stadium naming rights deal ever at that time — seats 72,000. On Monday, the average reseller price for a ticket to the game was over $6,000. More elaborate package deals, with pre- and post-game parties, food, drinks and entertainment, can run thousands more. For bargain hunters, events at the stadium kick off a week before the game itself. You can buy tickets to Super Bowl Opening Night for as little as $20 to watch the players and coaches meet with members of the media. For $699 you could attend a fancy tailgating event with NFL players that also has an open bar, DJ and catering by celebrity chef Guy Fieri.

Going the distance at home

You don't have to go to the game to spend money. "It's the day to invite over your friends and family to watch with you, and that means entertaining with food and drink," said Daina Falk, founder of HungryFan.com and author of "The Hungry Fan's Game Day Cookbook." Viewers spent an average of $82.19 on food, décor and team apparel for last year's Super Bowl, according to the National Retail Federation. (The group's estimates for 2017 are out January 24.) We also spend a lot on social lubricants. Super Bowl beer sales alone approach $600 million, according to InfoScan Reviews, and another $110 million is spent on liquor and spirits. "Beer is sort of the quintessential game-day beverage in America," Falk said. "While wine and other spirits have grown in popularity, it's tough to imagine they could overtake beer."

Then, of course, there's the commercials

Last year ad spending for commercials during the game totaled almost $380 million, according to Ad Age Datacenter. This year the cost of a 30-second spot exceeds $5 million, more than double what it was 10 years ago. And that's just the cost for showing the commercial, not creating it and paying the writers, editors, actors, set designers and special-effects artists involved.

"The spot itself may cost $5 million, but the investment in the spot goes much further," said Val DiFebo, CEO of the ad agency Deutsch NY, who's worked on "Got milk?" and Go Daddy Super Bowl ads and this year is creating work for Anheuser-Busch's Busch brand. "The Super Bowl can be more efficient than other mediums because of the visibility you get." She said the game is not only the world championship of football, it's also the world championship of advertising. "Nowhere else will you get a live audience — reaching roughly one-third of the U.S. population — that is eagerly anticipating both the game and the ads." Beyond reaching a huge audience, Super Bowl advertising has other benefits, DiFebo said. "Not only are people watching live, but they are also engaged and on fire, talking more about the commercials than about the games across multiple social channels. That 30-second ad during a three-hour game essentially has been extended to a three- to four-week opportunity to engage with the consumer."

Nowhere else will you get a live audience — reaching roughly one-third of the U.S. population — that is eagerly anticipating both the game and the ads. Val DiFebo CEO of the ad agency Deutsch NY

American icons like GM will be running ads during the big game, but plenty of brand-name public companies are tied to Super Bowl economics in less direct ways, noted investment advisor Brent Wilsey of Wilsey Asset Management in a pregame stock analysis. (He cautions against making stock market play-calls based on the big game.) Tiffany's has been producing the Vince Lombardi Trophy since Super Bowl 1 in 1967. The trophy is made from scratch every year and costs $50,000. Nike supplies the NFL with uniforms and sportswear for many loyal fans. Jersey purchases for the big game can be found at Dick's Sporting Goods. Makers of television screens, and their sellers like Best Buy, also benefit, as Americans use the game as an excuse to go bigger with their flat screens. Americans purchased 8.6 million new televisions leading up to the game last year, according to the National Retail Federation.

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