252

Number
$252$ (two hundred and fifty-two) is:
 * $2^2 \times 3^2 \times 7$


 * The $16$th of the $17$ positive integers for which the value of the Euler $\phi$ function is $72$:
 * $73, 91, 95, 111, 117, 135, 146, 148, 152, 182, 190, 216, 222, 228, 234, 252, 270$