Kurt Wilhelm Sebastian Hensel (29 December 1861 – 1 June 1941) was a German mathematician born in Königsberg.

Kurt and Paul's paternal grandparents were painter Wilhelm Hensel and composer Fanny Mendelssohn.

Both of Hensel's grandmothers and his mother were from Jewish families that had converted to Christianity.

Hensel studied mathematics in Berlin and Bonn, under the mathematicians Leopold Kronecker and Karl Weierstrass.

First described by him in 1897,[1] they became increasingly important in number theory and other fields during the twentieth century.