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The number 9,223,372,036,854,775,807 is an integer equal to 2 − 1. It has a factorization of , which is equal to == In computing == The number 9,223,372,036,854,775,807, equivalent to the hexadecimal value , 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 (, , or ) 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 2−1 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「9223372036854775807」の詳細全文を読む スポンサード リンク
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