We have obtained electric properties of PdropP from finite-field Moller-Plesset perturbation theory, density functional theory and coupled cluster techniques. Reference, near-Hartree-Fock values have been obtained with a very large (20s15p10d5f) uncontracted basis set consisting of 300 Gaussian-type functions. At the experimental equilibrium bond length of R-e = 1.8934 Angstrom we obtain self-consistent field values of 1.0682 ea(0)(2) for the quadrupole moment (Theta), -41.68 ea(0)(4) for the hexadecapole moment (Phi), 51.16 for the mean ((α) over bar) and 28.58 e(2)a(0)(2) E-h(-1) for the anisotropy of the dipole polarizability, and 16.5 x 10(3) e(4) a(0)(4)E(h)(-3) for the mean second dipole hyperpolarizability ((γ) over bar). Electron correlation reduces strongly the magnitude of the electric moments. Both components of the dipole polarizability are reduced by electron correlation, but a small increase is observed for the dipole hyperpolarizability. Our best post-Hartree-Fock values have been obtained with a [9s7p5d3f] basis set at the CCSD(T) level of theory: Theta = 0.4850 ea(0)(2), Phi = -31.25 ea(0)(4), (α) over bar = 49.20 and Deltaalpha = 28.02 e(2)a(0)(2)E(h)(-1), (γ) over bar = 16.8 x 10(3) e(4)a(0)(4)E(h)(-3). The bond-length dependence around R-e has been obtained for all properties. Conventional density functional theory methods predict dipole polarizabilities close enough to the most accurate CCSD(T) values but overestimate the second dipole hyperpolarizability. The mean dipole polarizability changes as alpha(NaK) > (α) over bar (AICl) > (α) over bar (Sis) > (α) over bar (P-2) > (α) over bar (Zn) for some isoelectronic, 30-electron systems. It is seen that the electric properties in the sequence N-2-->P-2-->As-2 display regular changes.