The Landau level spectra and the quantum Hall effect of ABA-stacked multilayer graphenes are studied in the effective-mass approximation. The low-energy effective-mass Hamiltonian may be partially diagonalized into an approximate block-diagonal form, with each diagonal block contributing parabolic bands except for an additional block describing Dirac-like bands with a linear dispersion in a multilayer with an odd number of layers.We fully include the band parameters and, taking into account the symmetry of the lattice, we analyze their effect on the block-diagonal Hamiltonian. Next-nearest-layer couplings are shown to be particularly important in determining the low-energy spectrum and the phase diagram of the quantum Hall conductivity by causing energy shifts, level anticrossings, and valley splitting of the low-lying Landau levels.