Marketing company CDG revealed on Monday that Hajime Isayama's Shingeki no Kyojin (Attack on Titan) manga has more than 66 million copies in print.

Isayama launched the manga in Bessatsu Shōnen Magazine in 2009, and Kodansha published the 22nd compiled book volume in Japan on April 7. Kodansha Comics publishes the series in print in English, and it released the 21st volume on April 18. Crunchyroll also publishes the manga in English digitally as new chapters are published in Japan.

The original manga has inspired a television anime, numerous spinoff manga, several novel series, a two-part live-action film project, a spinoff live-action television series, and an original video anime (OVA). It also inspired an anthology graphic novel featuring short stories from western comic artists.

The television anime's second season premiered on April 1. Funimation began streaming a simulcast version on the same day, and Crunchyroll is also streaming the series. The first 25-episode anime season aired from April-September 2013. Both Funimation and Crunchyroll streamed the first season as it aired in Japan, and Funimation released the series on home video in 2014. The first season also inspired two compilation anime films in 2014 and 2015. Two of the spinoff manga — Attack on Titan: No Regrets and Attack on Titan: Junior High — received anime adaptations of their own.