Solve $1+x+\frac{x^{2}}{2 !}+\frac{x^{3}}{3 !}+\cdots=e^{4}$ For X

Solve $1+x+\frac{x^{2}}{2 !}+\frac{x^{3}}{3 !}+\cdots=e^{4}$ for x.