1023 (number)
{{infobox number
| number = 1023
| divisor = 1, 3, 11, 31, 33, 93, 341, 1023
| unicode =
| greek prefix =
| latin prefix =
}}
1023 is the natural number following 1022 and preceding 1024.
Mathematics
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1023 is a number whose sum of digits is 6,{{OEIS link|A052220}} and is a sum of 5 consecutive primes (193, 197, 199, 211 and 223).{{OEIS link|A034964}}
It is a sub-perfect power (a perfect power minus 1) specifically 4^5 - 1 and 2^10 - 1.{{OEIS link|A045542}} The latter of these makes it a Mersenne number,{{OEIS link|A000225}} and both of these cause it to be palindromic when converted to bases 2 and 4 (as in both they are a string of 1's).{{OEIS link|A097856}}
It is a Stirling number of the second kind, specifically .{{OEIS link|A008277}}
There are 1023 polycubes with 7 cells (when counting reflections as distinct, which is standard).{{OEIS link|A000162}}
In other fields
=Computing =
Floating-point units in computers often run a IEEE 754 64-bit, floating-point excess-1023 format in 11-bit binary. In this format, also called binary64, the exponent of a floating-point number (e.g. 1.009001 E1031) appears as an unsigned binary integer from 0 to 2047, where subtracting 1023 from it gives the actual signed value.
1023 is the number of dimensions or length of messages of an error-correcting Reed-Muller code made of 64 block codes.{{OEIS link|A008949}}
=Technology=
The Global Positioning System (GPS) works on a ten-digit binary counter that runs for 1023 weeks, at which point an integer overflow causes its internal value to roll over to zero again.
1023 being , is the maximum number that a 10-bit ADC converter can return when measuring the highest voltage in range.