Puerto Rico is about 163 times smaller than Alaska.

Alaska is approximately 1,481,348 sq km, while Puerto Rico is approximately 9,104 sq km, making Puerto Rico 0.61% the size of Alaska. Meanwhile, the population of Alaska is ~710,231 people (2.4 million more people live in Puerto Rico).
Tip: This to-scale comparison of Alaska vs. Puerto Rico uses the Mercator projection, which distorts the size of regions near the poles.