Tithonia speciosa 'Torch' with female Papilio glaucus (Eastern tiger swallowtail)

Sounds like a great suggestion. I'll look for it next year.
When do they poop out and are the seeds they make sterile? Does it benefit by deadheading?

Since Tithonia is a tender annual, anything that pops out before the last freeze will die, so the effective germination start in the ground is the last freeze. This can be extended into the winter by pre-germinating in containers inside.
This is the first season so we haven't tested the produced seeds but we have no information that they would be sterile. Deadheading is indeed suggested to increase flowering and would also take care of self-seeding, although it may be useful to allow some seeds to mature for propagation. Also seeds are attractive to birds.

Plan to provide study stakes for Tithonia. Mine is at about 6' high today and still growing. Plant in groups of four or five set about 20" apart for a vibrant show of brilliant orange blossoms in full sun and covered with swallow tailed butterflies flitting about. Beautiful sight that stops traffic. Needs daily deadheading which is very easy. Sets viable seed heads much like sunflowers. A must plant annual which should be placed where all can enjoy the color. Lights up the neighborhood!