  We present a detailed analysis of the stellar content of the current version
of the XMM-Newton slew survey (XMMSL2). Since stars emit only a small fraction
of their total luminosity in the X-ray band, the stellar XMMSL2 sources ought
to have relatively bright optical counterparts. Therefore the stellar
identifications are obtained by an automatic crossmatch of the XMMSL2 catalog
with the first Gaia data release (Gaia DR1), the 2MASS and the Tycho2 catalogs.
The reliability of this procedure is verified by a comparison with the
individually classified Einstein Observatory medium sensitivity survey X-ray
sources and by a crossmatch with the Chandra Source Catalog. We identify 6815
of the 23252 unique XMMSL2 sources to be stellar sources, while 893 sources are
flagged as unreliable. For every counterpart a matching probability is
estimated based upon the distance between the XMMSL2 source and the
counterpart. Given this matching probability the sample is expected to be
reliable to 96.7 % and complete to 96.3 %. The sample contains stars of all
spectral types and luminosity classes, with late-type dwarfs having the largest
share. For many stellar sources the fractional contribution of the X-ray band
to the total energy output is found above the saturation limit of previous
studies ($L_\mathrm{X}/L_\mathrm{bol}=10^{-3}$), because the XMMSL2 sources are
more affected by flares due to their short exposure times of typically 6 s. A
comparison with the "Second ROSAT all-sky survey (2RXS) source catalog" shows
that about 25 % of the stellar XMMSL2 sources are previously unknown X-ray
sources. The results of our identification procedure can be accessed via
VizieR.
