use strict;
use warnings;
use 5.010;

my $str = 'XXXX - 12345 - - XXXXXXX XX - XXXXX XX TN6789';
my @pieces = split /\s+/, $str;

my $val1 = $pieces[2];
(my $val2 = $pieces[-1]) =~ s/^TN//;

say $val1;
say $val2;

my %hash = (
    'keyA' => $val1,
    'keyB' => $val2
);

say %hash;

--output:--
12345
6789
keyB6789keyA12345