Leonhard Euler

+20: Euler is among the most prolific and successful mathematicians in the history of the Mathematics.
+20: He made important contributions to complex analysis, Number theory, Graph theory, topology, applied mathematics.
+20: He was so prolific that exist at least 9 Euler's Theorems, 7 Euler's formulas, 10 Euler's equations and 2 Euler's conjectures.