290

Number
$290$ (two hundred and ninety) is:


 * $2 \times 5 \times 29$


 * The $21$st untouchable number after $2$, $5$, $52$, $88$, $96$, $120$, $124$, $\ldots$, $262$, $268$, $276$


 * The $28$th noncototient after $10$, $26$, $34$, $50$, $\ldots$, $244$, $260$, $266$, $268$, $274$:
 * $\nexists m \in \Z_{>0}: m - \map \phi m = 290$
 * where $\map \phi m$ denotes the Euler $\phi$ function


 * The $32$nd sphenic number after $30$, $42$, $66$, $70$, $\ldots$, $246$, $255$, $258$, $266$, $273$, $282$, $285$, $286$:
 * $290 = 2 \times 5 \times 29$


 * The $47$th nontotient:
 * $\nexists m \in \Z_{>0}: \map \phi m = 290$
 * where $\map \phi m$ denotes the Euler $\phi$ function