What does the fox say? Ka-ching at the moment, at least for some Halloween costume sellers and two Norwegian TV hosts who asked the question in a goofy video that landed them on U.S. talk shows and music charts.

Funny brothers Vegard and Bard Ylvisaker, known as Ylvis (ILL-vis), elevated the woodland creature in early September and have scored more than 150 million YouTube views of them prancing in fox suits singing: "Ring-ding-ding-ding-dingeringeding! Gering-ding-ding-ding-dingeringeding!"

That, coming so close to Halloween, has the mysteriously sounding fox going tail to tail for meme-of-the-holiday with twerking teddy bears, the more modest companions of the barely dressed Miley Cyrus at the Video Music Awards.

Spirit Halloween, with strong online sales and more than 1,050 stores across the country and Canada, is among those doing a brisk business in fox costumes, bushy tails and a furry head piece that looks remarkably like the one worn by the duo. Spirit sold out of some popular fox costumes and accessories online after the video struck, said Lisa Barr, the Halloween company's senior director of marketing.

"Although fox is selling out, Twerkin' Teddy (a tongue-out, bear decorated leotard) is selling out even faster," she said.

Yandy.com has seen a 227 percent increase over last year in sales of its exclusive Sexy Fox costume for women - into the hundreds at $245 each.

The fox, it appears, was enjoying a boost before the shaggy-haired Norwegians put together their disco-like gyrations to promote their late-night show, mockingly lamenting: "Ducks go blub and the seal goes ow, ow, ow. But there's one sound that no one knows. What does the fox say?"

The last thing the Ylvisakers expected was to become godfathers of the fox, a word - by the way - that translates to "rev" in Norwegian and is slang for joint, of the smoking variety.

"There have been speculations that we were under the influence at the time we wrote the song, but I'm sorry that's not the case," Bard, 32, deadpanned in a telephone interview from Oslo. "It would have sounded much more rock `n' roll. It's not that common over here. We're way more into alcohol than you guys. You do a lot of smoking. We don't."

How do the brothers feel about the fleet-footed animal, anyway? Is it a favorite?

It is now, Bard said. "Prior to that I would say I don't know. As long as it's not cats. I hate cats. I've always hated cats."

While Barr tries to shake the tune from her head, at least one Halloween merrymaker is more than a little giddy. Her name? Shelby Fox, who lives in Los Angeles.

"Oh yes, I'm very excited," said the 26-year-old, lifelong collector of select fox stuff. "When the video came out, so many people sent it to me. Personally, I think it's just a really cute animal."

Josh Saterman, a Macy's vice president and fashion director for millennial, said foxes have popped up on sweaters and graphic T-shirts as part of a broader "critter" trend.

"It's a moment around whimsy. It's a moment around laughter and so there's this play off of humor," he said.

Shelby Fox, for one, won't be going full-on fox for Halloween but will definitely riff on her namesake at a few parties she plans to attend.

"I think it's going to come more down to me wearing ears and a tail and doing some combination of more normal clothing. I'm definitely not doing the sexy fox or anything," she laughed.

Will she be getting a forest assist from any two-legged friends? "No. I'm on my own. The lone fox."

Sarah Segal was on vacation in Mexico when things got truly foxy after Ylvis. "I was in a taxi and the driver had the radio on," she said. "I heard this song and I thought to myself, `Is this a children's song?' It was so odd. I didn't know what it was, then I looked it up."

Then Segal, the public relations manager for CafePress.com - an online purveyor of customizable apparel, mugs, iPhone cases and paper goods - hunted down fox items on the site and came up with more than 2,000 for sale. That, she said, is a lot.

Comparatively speaking, though, "Twerking teddy has gone from zero to sixty for us. The fox has been more of a slow progression. People are obviously reacting to both of those. People like animals. Last year it was Grumpy Cat."

Jonathan Wasserstrum, the New York CEO of a company that helps businesses track down commercial rental space, found a funny hat and grabbed his co-founder to join the crowd outside the "Today" studios to watch Ylvis live in Midtown Manhattan. They also made a cardboard sign to wave.

"We're fans but we're not superfans," he explained of their sparse fox look. "It's just the silliness. You can walk around the office and any number of people will know the song."

So exactly what DOES the fox say? "I think foxes make a kind of yip noise," offered Shelby Fox.

The reality is more "Blair Witch Project" than Disney - a creepy, teeth-baring howl or bark, depending on species and mood.