Short answers, pulled from the story.
Brotherhood: Final Fantasy XV is a five-episode anime series set within the events of Final Fantasy XV that explores the backstories of Noctis Lucis Caelum and his three companions, Gladiolus Amicitia, Prompto Argentum, and Ignis Scientia. It was produced by Square Enix and A-1 Pictures and ran from the 30th of March to the 17th of September 2016.
Brotherhood: Final Fantasy XV was directed by Soichi Masui, written by Yuniko Ayana, and produced by Akio Ofuji. Music was composed by Yasuhisa Inoue and Susumi Akizuki. The series was co-produced by Square Enix and anime studio A-1 Pictures.
Brotherhood: Final Fantasy XV streamed for free on the official Final Fantasy XV YouTube channel and through the online service Crunchyroll. The series was deliberately made free to reach the widest possible audience, with its budget split between Final Fantasy XV's total production costs and projected physical sales.
Brotherhood: Final Fantasy XV has five episodes, each approximately ten to fifteen minutes long. The planned run was limited to five episodes, though producer Akio Ofuji stated that additional episodes could be produced depending on public reception.
As of November 2016, the first episode "Before the Storm" was the most watched video on the game's official YouTube channel with over 2,330,000 views. "Dogged Runner" had over 614,000 views, while the final episode drew just over 110,000 views.
Yes. All five episodes of Brotherhood: Final Fantasy XV were included on a Blu-ray disc in the Ultimate Collector's Edition of Final Fantasy XV, along with exclusive bonus scenes focusing on the character Lunafreya Nox Fleuret. The series was also included in the Final Fantasy XV Film Collection box set.