  We present updated measurements of the X-ray properties of the pulsar wind
nebula associated with the TeV $\gamma$-ray source HESS J1640-465 derived from
Chandra & NuSTAR data. We report a high $N_{H}$ value along line of sight,
consistent with previous work, which led us to incorporate effects of dust
scattering in our spectral analysis. Due to uncertainties in the dust
scattering, we report a range of values for the PWN properties (photon index
and un-absorbed flux). In addition, we fit the broadband spectrum of this
source and found evidence for spectral softening and decreasing unabsorbed flux
as we go to higher photon energies. We then used a one zone time dependent
evolutionary model to reproduce the dynamical and multi-wavelength spectral
properties of our source. Our model suggests a short spin-down time scale, a
relatively higher than average magnetized pulsar wind, a strong PWN magnetic
field and maximum electron energy up to PeV, suggesting HESS J1640-465 could be
a PeVatron candidate.
