You are limited to a 32-bit signed integer in Pawn (without considering any memory trickery) so the max number of digits you will encounter is 10, plus 1 to make room for the sign if negative plus one for null char so you can safely size the number string at 12.
Values storable in a 32-bit signed int are -2,147,483,647 to 2,147,483,647 which should be plenty.
More than plenty. Thank you!
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