1. Introduction; 2. The Riemann Zeta function; 3. Estimates; 4. Classical equivalences; 5. Euler's Totient function; 6. A variety of abundant numbers; 7. Robin's theorem; 8. Numbers which do not satisfy Robin's inequality; 9. Left, right and extremely abundant numbers; 10. Other equivalents to the Riemann hypothesis; Appendix A. Tables; Appendix B. RHpack mini-manual; Bibliography; Index. Skryť popis