Multiply $590$ and $44444444444$ to get $26222222221960$.
$$\frac{4}{\sqrt{26222222221960}}$$
Factor $26222222221960=2^{2}\times 6555555555490$. Rewrite the square root of the product $\sqrt{2^{2}\times 6555555555490}$ as the product of square roots $\sqrt{2^{2}}\sqrt{6555555555490}$. Take the square root of $2^{2}$.
$$\frac{4}{2\sqrt{6555555555490}}$$
Rationalize the denominator of $\frac{4}{2\sqrt{6555555555490}}$ by multiplying numerator and denominator by $\sqrt{6555555555490}$.
