About two Bernoulli experiment

Question

Say there are two Bernoulli random variables: $X_1$ and $X_2$ with different $\mu_1$ and $\mu_2$. Now let them each perform $N$ trials, my question is how to calculate the possibility such that $N(X_1) > N(X_2)$? $N()$ means the successful number of $X_1$ and $X_2$ in their $N$-time trials.