Maths problem :
$$(9^{62773} + 2)^{83721}$$ Now here is the rest of the problem. After finding the huge number I have to find its digital sum. If you don't know what that means just give me the answer to the problem. Please try to solve it also please tell me the method just try avoiding using $\log$.
I tried using $\log$ but as it was not allowed. I couldn't find a calculator which could do this.
First, you can ignore the powers of $9$ because they do not impact the digital sum. Now we are looking for $2^{83721} \pmod 9$. If you just compute the powers of $2 \pmod 9$ you will find they cycle. What is the cycle length? Now you just need the remainder of $83721$ divided by the cycle length.