Odegaard is working his way back from ankle injury.
Havertz told Sky Sports: "I don't know how long he is injured now, maybe two weeks, but every day, he's here every day, he's in the meetings and speaks to us.
"Yeah I think, I think he is the perfect captain for a team like us where we have like so many young players and still the players who can progress, and he is just there for everyone and not only off the pitch.
"To be honest when I came, before I came to Arsenal, I didn't think he would speak so much like in the dressing room and stuff like that. But he speaks a lot and in the dressing room before the game, stuff like that, and he is also always there on the pitch. You know, when the things are not going your way, you need someone to step up."
He added: "I think everyone has to step up when one of your most important players is missing and I think we do it quite well at the moment, we have some players um they now speak a lot in the dressing room, that helps.
"So, yeah we hope obviously Martin comes back very quickly but um yeah we have to do our job when he's not there."