At the moment The Doctor doesn't have a companion. However his last companion was Donna Noble. In the recent Easter special 'Planet of the Dead' he had a one day conpanion Lady Christina de Souza. He doesn't want to take another companion, because of how he lost Donna and Rose.
Amy Pond is the Doctor's companion at the moment.
Amy Pond is his only confirmed companion so far, River Song is back for an episode or two as well.
The eleventh Doctor will star in The Sarah Jane Adventures along with the third Doctor's companion Jo Grant, apart from that there are no plans to bring any former companions back to Doctor Who.
The sixth Doctor's companions were Peri Brown and Melanie Bush.
Doctor Who The Doctors Revisited - 2013 The Eleventh Doctor 1-11 is rated/received certificates of: UK:U
Matt Smith is the eleventh Doctor so therefore there have been 11 Doctors in cluding him.
3 doctors did - the 1st, the 5th and the 10th.
While those were the main doctors she appeared with, she was there in the Five Doctors (so she was with all the first five) and the Eleventh Doctor was in two episodes of the Sarah Jane Smith Adventures. So the answer is actually seven. :)
Doctor Who The Doctors Revisited - 2013 The Eleventh Doctor 1-11 was released on: UK: 16 November 2013 Australia: 24 November 2013 New Zealand: 24 November 2013 USA: 24 November 2013
"eleventh".
The eleventh Doctor hasn't regenerated, he's only been in two series so far.
No
It depends. If you count the first two K9s as two separate companions, then the first and fourth Doctors tie for 9 companions each (not counting characters who were only traveling with the Doctor for one story). Otherwise, it's the First Doctor.
The Armistice , the eleventh hour, of the eleventh day ,of the eleventh month