Find quality factor from a bode plot
Hertz or radians per second doesn't numerically affect Q just in case anyone calls me for working unitless: -

Lower 3dB point appears to be about 1884. Upper 3dB point appears to be 18840. Delta (for the approximate calculation of Q) is 18840 - 1884 = 16956. This means Q is approximately 6280/16956 = 0.37.

I don't know how you got 3865?