What is the decimal value of this $64-$bit two's complement number?$1111111111111111111111111111111111111111111111111111111111111000,1)-42)8$ten$3116$len$4)18\mathrm{.}446\mathrm{.}744\mathrm{.}073\mathrm{.}709\mathrm{.}551,6096$n