Polygons with integer angles

For how many integers $n \ge 3$ does a regular $n$ -gon have interior angles that are an integer number of degrees?

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The interior angle is $180 - 360/n$ . When is that an integer?
Need $n \mid 360$ with $n\ge3$ . Count divisors of $360=2^33^25$ and drop $1$ and $2$ .

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