Compressibility factor of a gas is greater than one indicates that 

$\mathrm{Z}=\frac{{\mathrm{V}}_{\mathrm{real}}}{{\mathrm{V}}_{\mathrm{ideal}}}$ 

According to the question, $\frac{{\mathrm{V}}_{\mathrm{real}}}{{\mathrm{V}}_{\mathrm{ideal}}}$>1 

Volume of ideal gas is 22.4 L, this means that ${\mathrm{V}}_{\mathrm{real}}>22.4 \mathrm{L}$

This means that volume is high, gaseous molecules are far apart and it is less compressible than ideal gas.