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 $1$, $4$, $9$, $16$, $25$, $36$, $49$, $64$, $81$, $100$, $121$, $144$, $169$, $196$, $225$:
 * $256 = 16 \times 16$


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


 * The $2$nd eighth power after $1$:
 * $256 = 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2$


 * The $27$th powerful number after $1$, $4$, $8$, $9$, $16$, $25$, $\ldots$, $144$, $169$, $196$, $200$, $216$, $225$, $243$


 * 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