Examples? Almost all great mathematicians before the middle of 19th century, beginning from Euclid (who wrote not only the Elements but also a book on Optics): Archimedes, Apollonius, Hero, Ptolemy,...,Kepler, Napier,..., Huygens, Newton,..., Euler, Gauss, Cauchy, Lagrange, Jacobi, Riemann,..., Klein, Poincare,..., and very many 20 century mathematicians: Fatou, Weyl, Hardy, Littlewood, Vladimir Arnold, Atiyah, Donald Knuth, ... too many of them to make a list of reasonable length.

Examples? Almost all great mathematicians before the middle of 19th century, beginning from Euclid (who wrote not only the Elements but also a book on Optics and another on Astronomy): Archimedes, Apollonius (who introduced epicycles to Astronomy), Hero, Ptolemy,...,Kepler, Napier,..., Huygens, Newton,..., Euler, Gauss (who spent most of his career doing geodesy, astronomy, magnetism, and also invented telegraph), Cauchy, Lagrange, Jacobi, Riemann (contributions to electrostatics, ellasticity and PDE),..., Klein (his great book on spinning tops), Poincare (celestial mechanics),..., and very many 20 century mathematicians: Fatou, Weyl, Littlewood, Vladimir Arnold, Atiyah, Donald Knuth, and even Hardy (who boasted that he is a pure mathematician:-) ... too many of them to make a list of reasonable length.

I would say that before 1850, a great mathematician who DID NOT contribute to applied mathematics is a rarity.

Almost all great mathematicians before the middle of 19th century, beginning from Euclid (who wrote not only the Elements but also a book on Optics): Archimedes, Hero,..., Huygens, Newton,..., Euler, Gauss, Cauchy, Lagrange, Jacobi, Riemann,..., Klein, Poincare,..., and very many 20 century mathematicians: Fatou, Weyl, Hardy, Littlewood, Vladimir Arnold, Donald Knuth, ... too many of them to make a list of reasonable length.

Examples? Almost all great mathematicians before the middle of 19th century, beginning from Euclid (who wrote not only the Elements but also a book on Optics): Archimedes, Apollonius, Hero, Ptolemy,...,Kepler, Napier,..., Huygens, Newton,..., Euler, Gauss, Cauchy, Lagrange, Jacobi, Riemann,..., Klein, Poincare,..., and very many 20 century mathematicians: Fatou, Weyl, Hardy, Littlewood, Vladimir Arnold, Atiyah, Donald Knuth, ... too many of them to make a list of reasonable length.