This phase III trial studies how well adding apalutamide, abiraterone acetate, and prednisone to the usual hormone therapy and radiation therapy works compared to the usual hormone therapy and radiation therapy in treating patients with node-positive prostate cancer after surgery. Radiation therapy uses high energy x-ray to kill tumor cells and shrink tumors. Androgens, or male sex hormones, can cause the growth of prostate cancer cells. Drugs, such as apalutamide, may help stop or slow the growth of prostate cancer cell growth by blocking the androgens. Abiraterone acetate blocks some of the enzymes needed for androgen production and may cause the death of prostate cancer cells that need androgens to grow. Prednisone may help abiraterone acetate work better by making tumor cells more sensitive to the drug. Adding apalutamide and abiraterone acetate with prednisone to the usual usual hormone therapy and radiation therapy after surgery may stabilize prostate cancer and prevent it from spreading or extend time without disease spreading compared to the usual approach.