Is 23,148,855,308,184,500 a magic number, or sheer chance?

magic-numbers
Roddy picture Roddy · Jul 15, 2009 · Viewed 38k times · Source

News reports such as this one indicate that the above number may have arisen as a programming bug.

A man in the United States popped out to his local petrol station to buy a pack of cigarettes - only to find his card charged $23,148,855,308,184,500.

That is $23 quadrillion (£14 quadrillion) - many times the US national debt.*

In hex it's $523DC2E199EBB4 which doesn't appear terribly interesting at first sight.

Anyone have any thoughts about what programming error would have caused this?

Answer

Guffa picture Guffa · Jul 15, 2009

Add the cents to the number and you get 2314885530818450000, which in hexadecimal is 2020 2020 2020 1250.

Do you see the pattern? The first six bytes have been overwritten by spaces (hex 20, dec 32).

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