I fail to see any benefit in the structure of your data structure. If you have keys with names that contain consecutive intergers, then that is a big red flag saying you might need an array instead. Try this instead:

use Data::Dumper;

my $customers = [
   map {
      {
         current => [ $_ ]
      }
   } (13, 110, 10, 102, 108, 130, 10, 107, 5, 210, 1, 160, 16)
];
 
print Dumper $customers;
[download]

print $customer->[8]->{current}->[0];
[download]

my @sorted = sort {
   $a->{current}->[0] <=> $b->{current}->[0]
} @$customer;

print Dumper \@sorted;
[download]

UPDATE: yes, i read that. I really do wish that you would have stated that 'cust1' was just a bogus key name. However, i still stand by my recommendation, unless you are doing more lookups than sorts. Leaving out code is fine, but don't leave out the details, please. "The actual data structure is much larger than it appears below but the following code is sufficient to describe the issue" in no way implies that "The keys of the top level hash are our actual customer names which I did not feel should be listed in this forum."

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)