With all the prime number fun going on over here, now seems a good chance to dust off and present an obfuscation that just needed a little polishing up.

Given a positive integer argument, this program will display all of its prime factors. 

 $;=pop;{$.=
 0;map{$;%$_
 or$.||=$_}2
 ..sqrt$;;;+
 $.||die$;-j
 .$/;warn$..
 $/;$;/=$.;n
 until+redo}

[download]
s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/

In reply to Prime Time for an Obfuscation by liverpole

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