Sometimes it is worth your while to consider why you are converting in the first place.

That string looks a lot like a scalar representation of localtime ... if you want seconds since the epoch started for a numerical comparison, better to use time in the first place, perhaps as in this (untested) snippet:

use strict;
use warnings;

my $eval_time = get_time_of_thing_i_am_checking();
my $now = time();
my $some_interval = 60 * 60 * 14;
if (($now - $eval_time) > $some_interval) {
  # do stuff
}  
else {
  print "Not enough time has elapsed.  Go fish.\n";
}
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