math-bignum-digit-length

math-bignum-digit-length is a variable defined in `calc.el'.
Its value is

9

• This variable may be risky if used as a file-local variable.

Documentation:
The length of a "digit" in Calc bignums.
If a big integer is of the form (bigpos N0 N1 ...), this is the
length of the allowable Emacs integers N0, N1,...
The value of 2*10^(2*MATH-BIGNUM-DIGIT-LENGTH) must be less than the
largest Emacs integer.