Hi, @sydneyschelvis! Did some digging for you, and the unofficial number I got was that it would be over 40 million songs. Maximum allowed in a single playlist is 9999, and maximum allowed to be saved on one device is 3333.
I hope this is helpful, and I hope you have a wonderful sunday filled with the music you love.
Hi, @sydneyschelvis. It's not an official number. I asked around fellow Rock Stars and moderators and this is the number that came up. I didn't get an absolute number, though, and I'm still trying to find a final number - I'd love to know to the song.
I don't believe you'll ever get an apsolute number, as Spotify is constently adding thousands of new songs each week. In my opinion, it's just better to get a yearly average, which is 40 million (which is the agreed estimate).