|Cardinal||nine quintillion two hundred twenty-three quadrillion three hundred seventy-two trillion thirty-six billion eight hundred fifty-four million seven hundred seventy-five thousand eight hundred seven|
(nine quintillion two hundred twenty-three quadrillion three hundred seventy-two trillion thirty-six billion eight hundred fifty-four million seven hundred seventy-five thousand eight hundred and seventh)
|Factorization||72 × 73 × 127 × 337 × 92737 × 649657|
The number 9,223,372,036,854,775,807, equivalent to the hexadecimal value 7FFF,FFFF,FFFF,FFFF16, is the maximum value for a 64-bit signed integer in computing. It is therefore the maximum value for a variable declared as a long integer (
) in many programming languages running on modern computers. The presence of the value may reflect an error, overflow condition, or missing value.
This value is also the largest positive signed address offset for 64-bit CPUs utilizing sign-extended memory addressing (such as the AMD x86-64 architecture, which calls this "canonical form" extended addressing). Being an odd value, its appearance may reflect an erroneous (misaligned) memory address. Such a value may also be used as a sentinel value to initialize newly allocated memory for debugging purposes.
The C standard library data type
time_t, used on operating systems such as Unix, is typically implemented as either a 32-bit or a 64-bit signed integer value, counting the number of seconds since the start of the Unix epoch (midnight UTC of 1 January 1970). Systems employing a 32-bit type are susceptible to the Year 2038 problem, so many implementations have moved to a wider 64-bit type, with a maximal value of 263−1 corresponding to a point in time 292 billion years from now.
Other systems encode system time as a signed 64-bit integer count of the number of ticks since some epoch date. On some systems (such as the Java standard library), each tick is one millisecond in duration, yielding a usable time range extending 292 million years into the future. On other systems (such as Win32), each tick is 100 nanoseconds long, yielding a time range of ±29,227 years from the epoch.
An error in the PayPal payment system in July 2013 accidentally debited $92 quadrillion from the account of Chris Reynolds. (The exact amount debited was US$92,233,720,368,547,940.25, just $182.18 more than 263−1 cents, resulting in a net balance of −US$92,233,720,368,547,800.00). PayPal corrected the error, and offered to make a donation to a charity of Reynold's choice.
In 2014 the number of views on the video Gangnam Style on YouTube began approaching the maximum value of a signed 32-bit integer (231−1, or 2,147,483,647). So Google claimed they were forced to upgrade their database to use 64-bit data fields to hold the number of views for a video. Two days later Google admitted that it was only a joke.
- "PayPal Glitch Actually Put Man $92 Quadrillion in the Red". Daily Finance. 2013. Retrieved 18 September 2013.
- "We never thought a video would be watched in numbers greater than a 32-bit integer". 2014. Retrieved 21 April 2015.
- Assar, Yijith (5 Dec 2014). "No, 'Gangnam Style' Didn't Break YouTube. We Did the Math". Wired. Condé Nast Web Sites. Retrieved 25 December 2014.
- "Gangnam Style' busts YouTube's view counter? Not so fast". Retrieved 21 April 2015.