IntToStr Error

This is really causing some problems for me...
IntToStr only works for up to a 10 digit number.

SCAR Code:

begin
  WriteLn(IntToStr(Length(IntToStr(1))));
end.

Try this out and just change the number up until you are past 10 digits.

That's because an integer can only hold a value of up to 2147483647.

EDIT: I forgot to mention that if you use Int64ToStr, you can input a value of up to 9223372036854775807.

Seems very random...
But 9223372036854775807 happens to be high enough to deal with my project! =)
So thanks.