A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton-proton collisions at √s = 13 TeV. The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9 fb^-1. The measurement is performed for the ℓνjj final state (with ℓν indicating a lepton-neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass m_jj > 120 GeV and transverse momenta p_Tj > 25 GeV. The cross section of the process is measured in the electron and muon channels yielding σ_EW(Wjj) = 6.23 ± 0.12 (stat) ± 0.61 (syst) pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are -2.3 < c_WWW/Λ² < 2.5 TeV^-2, -8.8 < c_W/Λ² < 16 TeV^-2, and -45 < c_B/Λ² < 46 TeV^-2. These results are combined with the CMS EW Zjj analysis, yielding the constraint on the c_WWW coupling: -1.8 < c_WWW/Λ² < 2.0 TeV^-2.