Top quark mass and properties with ATLAS

The top quark plays a unique role among other known quarks as it decays before it forms hadronic bound states. Thus, studying its properties provides interesting opportunity to access properties of a bare quarks directly. The latest measurements of these properties with the ATLAS detector at the LHC are presented. Measurements sensitive to $Wtb$ vertex are summarized and compared to the best theoretical calculations. Effects of colour reconnection on the jet variables in top quark events are presented Limits on the flavour-changing neutral currents are discussed. The latest top quark decay width and mass measurements are reported.