  We report theoretical determination of the dipole polarizability of the neon
atom, including its frequency dependence. Corrections for the relativistic,
quantum electrodynamics, finite nuclear mass, and finite nuclear size effects
are taken into account. We obtain the value $\alpha_0=2.66080(36)$ for the
static polarizability, and $\alpha_2=2.850(7)$ and $\alpha_4=4.932(14)$ for the
first two polarizability dispersion coefficients (Cauchy moments); all values
are in atomic units (a.u.). In the case of static polarizability, our result
agrees with the best experimental determination [C. Gaiser and B. Fellmuth,
Phys. Rev. Lett. 120, 123203 (2018)], but our estimated uncertainty is
significantly larger. For the dispersion coefficients, the results obtained in
this work appear to be the most accurate to date overall compared to published
theoretical and experimental data. We also calculated the static magnetic
susceptibility of the neon atom, needed to obtain the refractive index of
gaseous neon. Our result, $\chi_0 = -8.484(19) \cdot 10^{-5}$ a.u., is about 9%
larger in absolute value than the recommended experimental value [CRC Handbook
of Chemistry and Physics, CRC Press, 2019, p. 4-145].
