Geometry optimization is efficient using generalized Gaunt coefficients, which significantly limit the amount of cross differentiation for multi-center integrals of highangular-momentum solid-harmonic basis sets. The geometries of the most stable C 240 , C 540 , C 960 , C 1500 , and C 2160 icosahedral fullerenes are optimized using analytic densityfunctional theory (ADFT), which is parameterized to give the experimental geometry of C 60 . The calculations are all electron, the orbital basis set includes d functions and the exchange-correlation-potential basis set includes f functions. The largest calculation on C 2160 employed about 39000 basis functions.