Can i get number of participants?

Can i get number of participants of room without loading iframe? I need number of participants who entered the room. I’ve used to get this number using jitsi API like this:
const domain = “”;
const options = {
roomName: “roomName”
const api = new JitsiMeetExternalAPI(domain, options);

		setInterval(function() {
			let numberOfParticipants = api.getNumberOfParticipants();
		}, 10000);

But it also creates this room iframe. I don’t need iframe. I researched a couple of forums and topis but I can’t find it out. If I dispose api like this:


it’s not working, I can’t get number of participants. Anybody can help?