Investopedia / Matthew Collins Euler’s number (e), 2.71828..., is one of the most important constants in mathematics. It's a non-repeating number that never ends. It's found in many contexts ...

In mathematics the natural logarithm \({\log _e}x\) is usually written as \(\ln x\). Like \(\pi\), \(e\) is a mathematical constant and has many applications in mathematics, particularly with logs.