324

Number
$324$ (three hundred and twenty-four) is:


 * $2^2 \times 3^4$


 * The $18$th square number after $1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289$:
 * $324 = 18^2$


 * The $26$th untouchable number after $2, 5, 52, 88, 96, 120, 124, \ldots, 262, 268, 276, 288, 290, 292, 304, 306, 322$.