pack and unpack can just let you do what you want, in Perl there is not like an intrinsic way to convert between binary and decimal but pack and unpack can allow you to do the interchanging...

my $decimal = 4;
$binary=unpack("B32", pack("N",$decimal));
print $binary;
print "\n";
my $newdecimal=unpack("N",pack("B32",$binary));
print $newdecimal;

# 32 in the template means the binary number will have 32 places
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