I added my followers on twitter and facebook, they are 5000 in total. *Special note the word used to describe accounts that are connected to you changes on each platform. On twitter they are followers, Facebook we call them friends and on LinkedIn they are connections. I could have also said "they are 5000 persons" but since accounts are not limited to persons I decided to use in total to make it more ambiguous.

the number of all the followers in Twitter and Facebook is 5000 people.

I add up all the followers of Twitter and Facebook,the answer is 5000 people.