256

Number
$256$ (two hundred and fifty-six) is:


 * $2^8$


 * In binary:
 * $10 \, 000 \, 000$


 * In hexadecimal:
 * $100$


 * The $16$th square number after $1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225$:
 * $256 = 16^2$


 * The $4$th fourth power after $1, 16, 81$:
 * $256 = 4 \times 4 \times 4 \times 4$


 * The $9$th almost perfect number after $1, 2, 4, 8, 16, 32, 64, 128$:
 * $\sigma \left({256}\right) = 511 = 2 \times 256 - 1$


 * The $10$th positive integer after $64, 96, 128, 144, 160, 192, 216, 224, 240$ with $6$ or more prime factors:
 * $256 = 2 \times 2 \times 2 \times 2 \times 2 \times 2 \left({\times \, 2 \times 2}\right)$


 * The $3$rd positive integer after $128, 192$ with $7$ or more prime factors:
 * $256 = 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2 \left({\times \, 2}\right)$

The $3$rd (and possibly last) power of $2$ after $1, 4$ which is the sum of distinct powers of $3$:
 * $256 = 2^8 = 3^0 + 3^1 + 3^2 + 3^5$

Also see