We introduce the notion of quasi-triangular anti-dendriform bialgebras, which can be induced by the solutions of the AD-YBE whose symmetric parts are invariant. A factorizable anti-dendriform bialgebra leads to a factorization of the underlying anti-dendriform algebra. Moreover, relative Rota-Baxter operators with weights are introduced to characterize the solutions of the AD-YBE whose symmetric parts are invariant. Finally, we interpret factorizable anti-dendriform bialgebras in terms of quadratic Rota-Baxter anti-dendriform algebras.