2187

Number
$2187$ (two thousand, one hundred and eighty-seven) is:
 * $3^7$


 * The $3$rd seventh power after $1$, $128$:
 * $2187 = 3 \times 3 \times 3 \times 3 \times 3 \times 3 \times 3$


 * Thus in ternary:
 * $2187_{10} = 10 \, 000 \, 000_3$


 * The $4$th term of a sequence of $17$ consecutive integers all of which are not coprime with the product of the other $16$:
 * $2187 \mathrel \not \perp \displaystyle \prod_{\substack {2184 \mathop \le k \mathop \le 2200 \\ k \mathop \ne 2187} } k$


 * The $7$th power of $3$ after $(1)$, $3$, $9$, $27$, $81$, $243$, $729$:
 * $2187 = 3^7$