The world, meaning Earth, has a diameter of about 12,756 kilometers (7,926 miles) at the equator. Its circumference is approximately 40,075 kilometers (24,901 miles). The surface area of Earth is about 510 million square kilometers (197 million square miles), with around 71% covered by oceans and 29% by land. Earth is the fifth largest planet in our solar system, slightly flattened at the poles and bulging at the equator due to its rotation.