#!/usr/bin/perl

use strict;
use warnings;

my $secs_per_day = 60 * 60 * 24;
while (my $line = <DATA>)
{
    chomp $line;
    if ($line =~ m/MTIME:\s+(.*)/)
    {
        my $time = $1;
        my $secs = $time * $secs_per_day;
        print "$time days is $secs second(s)\n";
    }
}

__END__

Output:
1.15740740740741e-05 days is 1 second(s)
0.000104166666666667 days is 9.00000000000003 second(s)


__DATA__
MTIME: 1.15740740740741e-05
MTIME: 0.000104166666666667