\[\boxed{\mathbf{523}.}\]
\[1)\ \sqrt[4]{x^{2} - 2x}\]
\[x^{2} - 2x \geq 0\]
\[x(x - 2) \geq 0\]
\[x \leq 0;\ \ x \geq 2.\]
\[2)\ \sqrt[3]{x^{3} - x^{2} - x - 1}\]
\[x - любое\ число.\]
\[3)\ \left( x^{2} - 3x - 4 \right)^{\frac{1}{6}}\]
\[x^{2} - 3x - 4 \geq 0\]
\[(x + 1)(x - 4) \geq 0\]
\[x \leq - 1;\ \ x \geq 4.\]
\[4)\ \left( x^{3} - x^{2} + x \right)^{\frac{1}{3}}\ \]
\[x - любое\ число.\]