Find the dissimilar number among the options.

Let's analyze the mathematical properties of the given numbers:
* $343=7^3$ (Cube of 7)
* $512=8^3$ (Cube of 8)
* $216=6^3$ (Cube of 6)
* $169=13^2$ (Square of 13)

Since 343, 512, and 216 are perfect cubes, whereas 169 is a perfect square, 169 is the dissimilar number.