  We present a detailed direct numerical simulation of statistically steady,
homogeneous, isotropic, two-dimensional magnetohydrodynamic (2D MHD)
turbulence. Our study concentrates on the inverse cascade of the magnetic
vector potential. We examine the dependence of the statistical properties of
such turbulence on dissipation and friction coefficients. We extend earlier
work sig- nificantly by calculating fluid and magnetic spectra, probability
distribution functions (PDFs) of the velocity, magnetic, vorticity, current,
stream-function, and magnetic-vector-potential fields and their increments. We
quantify the deviations of these PDFs from Gaussian ones by computing their
flatnesses and hyperflatnesses. We also present PDFs of the Okubo-Weiss
parameter, which distin- guishes between vortical and extensional flow regions,
and its magnetic analog. We show that the hyperflatnesses of PDFs of the
increments of the stream-function and the magnetic vector potential exhibit
significant scale dependence and we examine the implication of this for the
multiscaling of structure functions. We compare our results with those of
earlier studies.
