There is no limit to the number of tracks you can upload to your Audius profile, so you can freely share your music with your listeners without any limitations!
Please note that while there is no limit on the duration of your tracks, there is a file size limit for each upload, which is currently set at 200MB. See supported file formats for details. If you have a long mix that exceeds this limit, consider converting it to a 320kbps mp3 file before uploading to ensure it works.