C:\>perl -MMath::MPFR -le "$x=Math::MPFR->new(6 ** 6); print 6 ** $x;
2.6591197721532269e36305

C:\>perl -MMath::MPFR -le "$x=Math::MPFR->new(7 ** 7); print 7 ** $x;
3.7598235267837884e695974