No. Gandalf leaves the dwarves several times in the book, always returning, seemingly, just in time to save the dwarves from some terrible danger.
There were 13 plus Gandalf (the grey)
The book starts with Bilbo Baggins meeting Gandalf the Grey. There was a tea party that Gandalf arranged, pulling in 13 dwarves with him.
At the Unexpected Party, when gandalf introduced the 13 dwarves to Bilbo.
The one item that Gandalf is looking for is a Burglar for the dwarves, to make the number 14 instead of 13.
There were 13 dwarves. Bilbo was added to the party to make it 14 and avoid having an unlucky number.
There were already thirteen dwarves and the only reason they needed another to accompany them was due to thirteen being an unfortunate number. Bilbo was made the fourteenth mainly because of the unlucky number 13.
When? At the beginning, Gandalf the Grey chats to Bilbo saying he is looking for someone to go on an adventure. Bilbo, being timid at the start, is a little rude to Gandalf, but invites him to afternoon tea. Gandalf laughs and with his staff marks the front door "burglar for hire, etc". Later a knock on the door and after a while 13 dwarfs and Gandalf are in Bilbo's Bag End residence: Dwalin, Balin, Fili, Kili, Gloin, Oin, Ori, Nori, Dori, Bifur, Bofur, Bombur, and Thorin Oakenshield. During the adventure Bilbo is separated numerous times from the dwarfs, and aids them in their escapades with his new found confidence and bravery and his magical ring.
"You asked me to find the fourteenth man for your expedition, and I chose Mr. Baggins. Just let anyone say I chose the wrong man or the wrong house, and you can stop at thirteen and have all the bad luck you like, or go back to digging coal."Hope that answers it for you.
Bilbo the Hobbit and Gandalf the Wizard are accompanied by 13 dwarves: Thorin Oakenshield, Balin and Dwalin, Kili and Fili (Thorin's nephews), Ori, Nori and Dori, Oin and Gloin (the father of Gimli the Dwarf in the Lord of the Rings), Bifur, Bofur and Bombur. There are many other dwarves in the story, but they appear pretty much only peripherally as warriors in the Battle of Five Armies, or anecdotally from other stories.
13.
Perhaps the question would be "who does Bilbo accompany on a trip." Bilbo travels with Gandalf the wizard and thirteen dwarves: Thorin Oakenshield (their leader), Dwalin, Balin, Gloin, Oin, Dori, Ori, Nori, Bifur, Bofur, Bombur, Fili, and Kili. This not including ponies.
13 dwarvesThorinBalinDwalinKiliFiliBomburOriDoriNoriOinGloinBifurBofurThirteen.