Saint Vincent and the Grenadines is about 644 times smaller than Michigan.

Michigan is approximately 250,493 sq km, while Saint Vincent and the Grenadines is approximately 389 sq km, making Saint Vincent and the Grenadines 0.16% the size of Michigan. Meanwhile, the population of Michigan is ~9.9 million people (9.8 million fewer people live in Saint Vincent and the Grenadines).
Tip: This to-scale comparison of Michigan vs. Saint Vincent and the Grenadines uses the Mercator projection, which distorts the size of regions near the poles.