Well, I would use \b, 
say "$_: ", /\b(10000|[1-9][0-9]{0,3})\b/ ? "Y" : "N"
        for qw{240 2 3600 1 10000 0 0000 19999 999999999};

[download]
Same as your result: 
240: Y
2: Y
3600: Y
1: Y
10000: Y
0: N
0000: N
19999: N
999999999: N

[download]
updated: made capturing group

In reply to Re^3: Regex question by Marshall
in thread Regex question by Umdurman

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