What is the total number of votes in the electoral votes?

Overall there are a total of 538 electors and so 538 electoral votes.

Each state gets one electoral vote for each member of the House of Representatives and two electoral votes for the number of Senators. The number of members in the House of Representatives was fixed at 435 in 1911 and there are two senators from each state, for a total of 535 votes from all of the states. The District of Columbia get 3 votes to make the grand total 538.

It follows that the majority required to elect is 270 votes. (538/2 + 1 = 270)