= Solution
The supplied integral equation has <elliptic-curve discriminant> $\Delta=-11$. It therefore has <good reduction> at every $p\ne11$. At eleven its discriminant has <valuation> one. Under a change of <Weierstrass equation of an elliptic curve>, discriminant valuations differ by a multiple of twelve. A good integral model would have valuation zero, which is impossible. This is the <discriminant valuation obstruction to good reduction>; it also shows the displayed model is minimal at eleven. Hence
$$
\boxed{\text{The good primes are precisely all primes except }11.}
$$
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