Video · What do 5, 13 and 563 have in common? TwitterShare on Facebook962 873 625 views Numberphile - August 3, 2014 Science Numberphile More Videos The Mind-Blowing Base 13 Function – Numberphile Science · 5 days ago The Big Daddy of Infinite Integrals – Numberphile Science · 3 weeks ago The Stein Paradox – Numberphile Science · 4 weeks ago The Stein Paradox – Numberphile Science · 4 weeks ago The 9-sided Enneahedron – Numberphile Science · June 22, 2025 A simple equation that behaves weirdly – Numberphile Science · June 17, 2025 A Problem with Infinite Hotel Keys – Numberphile Science · May 16, 2025 Cardioids in Coffee Cups – Numberphile Science · April 20, 2025