Tools>Mass properties>Volume is incorrect

I created a solid sphere by revolving a semi circle.

The sketch shows the diameter = 29.22.

Tools>Section properties>Area of semi circle = 335.

Tools>Mass properties>Volume = 13062.

I think the volume of a sphere = 4/3 Pi Radius cubed, which when Radius = 14.61, is 4158.

Did SW get it wrong or what?

SolidworksGeneral