No country is crossed by both the Equator and the Greenwich meridian.
The Equator is the line of latitude at 0 degrees, dividing Earth into the Northern and Southern hemispheres. The Greenwich meridian is the conventional prime meridian at 0 degrees longitude, running through Greenwich in London. Their intersection lies in the Gulf of Guinea, in the Atlantic Ocean, rather than on land.
Several countries are crossed by the Equator, including Ecuador, Colombia, Brazil, São Tomé and Príncipe, Gabon, the Republic of the Congo, the Democratic Republic of the Congo, Uganda, Kenya, Somalia, Indonesia, and Kiribati. The Greenwich meridian crosses countries including the United Kingdom, France, Spain, Algeria, Mali, Burkina Faso, Togo, and Ghana. Ecuador is often guessed because its name refers to the Equator, but it is nowhere near the Greenwich meridian.