The general sextic equation
can be solved in terms of Kampé de Fériet functions, and a restricted class of sextics can be solved in terms of generalized hypergeometric functions in one variable using Klein's approach to solving the quintic equation.
The general sextic equation
can be solved in terms of Kampé de Fériet functions, and a restricted class of sextics can be solved in terms of generalized hypergeometric functions in one variable using Klein's approach to solving the quintic equation.
Weisstein, Eric W. "Sextic Equation." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/SexticEquation.html