\[ y'(x)=\frac {x^3 \sqrt {x^2+y(x)^2}+y(x)}{x} \] ✓ Mathematica : cpu = 0.118584 (sec), leaf count = 20
\[\left \{\left \{y(x)\to x \sinh \left (\frac {1}{3} \left (x^3+3 c_1\right )\right )\right \}\right \}\] ✓ Maple : cpu = 3.871 (sec), leaf count = 30
\[\ln \left (\sqrt {y \relax (x )^{2}+x^{2}}+y \relax (x )\right )-\frac {x^{3}}{3}-\ln \relax (x )-c_{1} = 0\]