Actually, yes, but not perfectly round as shown in this picture. The GOCE mission of the European Space Agency (ESA) has accurately measured the circumference of the earth. The colors represent the differences in altitude (+ 100 meters) of an ideal sphere. The accurate representation of the Earth’s surface is called geoid. The blue areas represent the hollow and red zones and gold, the higher areas.
For ESA, “A precise model of Earth’s geoid is crucial for deriving accurate measurements of ocean circulation, sea-level change and terrestrial ice dynamics. The geoid is also used as a reference surface from which to map the topographical features on the planet. In addition, a better understanding of variations in the gravity field will lead to a deeper understanding of Earth’s interior, such as the physics and dynamics associated with volcanic activity and earthquakes.”