In the top left quarter of circle we can observe that
$$\left(3^2+4^2\right)\times3\ =\ 75$$
In the top right corner
$$\left(7^2+9^2\right)\times3\ =\ 390$$
In the bottom left corner
$$\left(11^2+8^2\right)\times3\ =\ 555$$
In the bottom right corner
$$\left(13^2+5^2\right)\times3\ =\ 582$$
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