728
Jump to navigation
Jump to search
Number
$728$ (seven hundred and twenty-eight) is:
- $2^3 \times 7 \times 13$
- The $37$th Smith number after $4$, $22$, $27$, $58$, $\ldots$, $576$, $588$, $627$, $634$, $636$, $645$, $648$, $654$, $663$, $666$, $690$, $706$:
- $7 + 2 + 8 = 2 + 2 + 2 + 7 + 1 + 3 = 17$
- The smaller of the $1$st pair of Smith brothers:
- $7 + 2 + 8 = 2 + 2 + 2 + 7 + 1 + 3 = 17$, $7 + 2 + 9 = 3 + 3 + 3 + 3 + 3 + 3 = 18$
Also see
Sources
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $728$