Swift J1822.3 - 1606 was discovered on 2011 July 14 by the Swift Burst Alert Telescope following the detection of several bursts . The source was found to have a period of 8.4377 s and was identified as a magnetar . Here we present a phase-connected timing analysis and the evolution of the flux and spectral properties using RXTE , Swift , and Chandra observations . We measure a spin frequency of 0.1185154343 ( 8 ) s ^ { -1 } and a frequency derivative of -4.3 \pm 0.3 \times 10 ^ { -15 } at MJD 55761.0 , in a timing analysis that include significant non-zero second and third frequency derivatives that we attribute to timing noise . This corresponds to an estimated spin-down inferred dipole magnetic field of B \sim 5 \times 10 ^ { 13 } G , consistent with previous estimates though still possibly affected by unmodelled noise . We find that the post-outburst 1–10 keV flux evolution can be characterized by a double-exponential decay with decay timescales of 15.5 \pm 0.5 and 177 \pm 14 days . We also fit the light curve with a crustal cooling model which suggests that the cooling results from heat injection into the outer crust . We find that the hardness-flux correlation observed in magnetar outbursts also characterizes the outburst of Swift J1822.3 - 1606 . We compare the properties of Swift J1822.3 - 1606 with those of other magnetars and their outbursts .