And here's a version with Data::Dumper and some config vars that also works.

#!/usr/bin/perl -l

use strict; # https://perlmonks.org/?node_id=11133064
use warnings;

my $template = 'd<';
my $nv = 2.4;
$nv = 4135;                     # NOTE errors for this number
my $p = pack $template, $nv;
use Data::Dumper;
$Data::Dumper::Terse = $Data::Dumper::Useqq = 1;
my $s = Dumper $p;
print ">$s<\n";

system $^X, '-wle', "use strict; print unpack('H*', $s);";
[download]

Outputs:

>"\0\0\0\0\0'\260\@"
<

000000000027b040
[download]

note that it adds a newline, but perl doesn't care.