Answer:
8,275,842 digits
Step-by-step explanation:
One more than the floor of the logarithm to the base 37 gives the number of digits. The change of base formula can be used.
[tex]\log_{37}{(2^{43112609}-1)}\approx\dfrac{43112609\log{2}}{\log{37}}\approx 8275841.2[/tex]
Expressed in the base-37 number system, P has 8275842 digits.