2485

Number
$2485$ (two thousand, four hundred and eighty-five) is:
 * $5 \times 7 \times 71$


 * The $70$th triangular number after $1$, $3$, $6$, $10$, $15$, $\ldots$, $1891$, $1953$, $2016$, $2080$, $2145$, $2211$, $2278$, $2346$, $2415$:
 * $2485 = \ds \sum_{k \mathop = 1}^{70} k = \dfrac {70 \times \paren {70 + 1} } 2$