% /opt/v5.36.0/bin/perl -MMath::BigInt -wle '$z0 = Math::BigInt->new(2)**64; for my $i (0..12) { $zi = $z0 + 2**$i; $ni = "$zi"; $d = ($ni == ~0) ? "same" : "differ"; print "$i: $d" }'
0: same
1: same
2: same
3: same
4: same
5: same
6: same
7: same
8: same
9: same
10: same
11: same
12: differ
%