Try this one.

use strict;
use warnings;
use File::Copy;

my (@files, $file, $folder_name);
opendir(DIR, ".") or die "Can't Open Current Directory: $!";
@files = grep /\d{6}\.txt$/, readdir(DIR);
close DIR;


foreach $file(@files){
    if($file =~ /(\d{6})\.txt$/){
        $folder_name = $1;
        mkdir $folder_name;
        move  $file, "\./$folder_name/";
    }
}
[download]

Thanks,

Rajesh.K

Edit: g0n - replaced pre tags with code tags