How a Single Number Threatens Technology
2,147,483,647 is almost too much for some computers to handle
By Matt Cantor,  Newser User
Posted May 10, 2015 2:30 PM CDT
Recent reports pointed to concerns over the Boeing 787 that could be tied to the number 2,147,483,647.   (AP Photo/Nam Y. Huh)

(Newser) – As complex and incredible as our latest gadgets are, they can be foiled by something very simple: a number that's just too big. The BBC explains the phenomenon in terms of an odometer that only goes up to 99,999 miles. Drive another mile, and it would roll to zero again, and start counting from there. What is known as "integer overflow" can, in some cases, prompt disaster, the BBC notes. Case in point: a European Space Agency rocket that exploded shortly after it launched because velocity readings were beyond its capacity. In other cases, the result is comical. Take, for instance, the 105-year-old woman who got an invitation to preschool because she was born in '07—though not 2007, as the software involved expected. One number in particular is a problem for many of today's systems: 2,147,483,647, a number with its own Wikipedia page.

It's the highest number that a "32-bit signed register," as many systems run, can handle; the limit exists thanks to a need for digital efficiency, an expert tells the BBC. YouTube saw the problem firsthand: "We never thought a video would be watched in numbers greater than a 32-bit integer (=2,147,483,647 views), but that was before we met PSY," the site noted, referring to the musician whose "Gangnam Style" video "broke" the counter. (As Wired explained in 2014, YouTube figured out a fix by going from 32-bit integers to 64-bit, so the view limit is now in the quintillions.) More worryingly, the Boeing 787 Dreamliner may encounter a problem if its equipment has been left running for 2,147,483,647 hundredths of a second, or 248 days. And there are fears comparable to those surrounding the Y2K bug centered on the year 2038. Fortunately, experts are on the lookout for such issues. (Click to see how a "leap second" brought down a chunk of the Web.)