3439

Number
$3439$ (three thousand, four hundred and thirty-nine) is:


 * $19 \times 181$


 * The magic constant of a magic square of order $19$, after $1$, $(5)$, $15$, $34$, $\ldots$, $870$, $1105$, $1379$, $1695$, $2056$, $2465$, $2925$:
 * $\ds 3439 = \dfrac 1 {19} \sum_{k \mathop = 1}^{19^2} k = \dfrac {19 \paren {19^2 + 1} } 2$