570

Number
$570$ (five hundred and seventy) is:


 * $2 \times 3 \times 5 \times 19$


 * The $18$th integer $n$ after $1$, $3$, $15$, $30$, $35$, $56$, $70$, $78$, $105$, $140$, $168$, $190$, $210$, $248$, $264$, $357$, $420$ with the property that $\map \tau n \divides \map \phi n \divides \map \sigma n$:
 * $\map \tau {570} = 16$, $\map \phi {570} = 144$, $\map \sigma {570} = 1440$


 * The $23$rd integer after $7$, $13$, $19$, $35$, $38$, $\ldots$, $223$, $253$, $285$, $305$, $350$, $380$, $410$, $475$, $487$ the decimal representation of whose square can be split into two parts which are each themselves square:
 * $570^2 = 324 \, 900$; $324 = 18^2$, $900 = 30^2$