Saint Lucia is about 407 times smaller than Michigan.

Michigan is approximately 250,493 sq km, while Saint Lucia is approximately 616 sq km, making Saint Lucia 0.25% the size of Michigan. Meanwhile, the population of Michigan is ~9.9 million people (9.7 million fewer people live in Saint Lucia).
Tip: This to-scale comparison of Michigan vs. Saint Lucia uses the Mercator projection, which distorts the size of regions near the poles.