512

Number
$512$ (five hundred and twelve) is:
 * $2^9$


 * The $8$th cube number after $1, 8, 27, 64, 125, 216, 343$:
 * $512 = 8 \times 8 \times 8$


 * The $10$th almost perfect number after $1, 2, 4, 8, 16, 32, 64, 128, 256$:
 * $\sigma \left({512}\right) = 1023 = 2 \times 512 - 1$