8,212,890,625

Number
$8 \, 212 \, 890 \, 625$ is:


 * $5^{10} \times 29^2$


 * The $90 \, 625$th square number:
 * $8 \, 212 \, 890 \, 625 = 90 \, 625 \times 90 \, 625$


 * The $19$th automorphic number after $1$, $5$, $6$, $25$, $76$, $376$, $625$, $9376$, $\ldots$, $12 \, 890 \, 625$, $87 \, 109 \, 376$, $212 \, 890 \, 625$, $787 \, 109 \, 376$, $1 \, 787 \, 109 \, 376$:
 * $8 \, 212 \, 890 \, 625^2 = 67 \, 451 \, 572 \, 41\mathbf {8 \, 212 \, 890 \, 625}$
 * and the $2$nd of the only $2$ such with $10$ digits.