e (mathematical constant)
![](/Images/godic/202501/12/Euler's_formula.svg4407.png")
![The effect of earning 20% annual interest on an initial $1,000 investment at various compounding frequencies](/Images/godic/202501/12/Compound_Interest_with_Varying_Frequencies.svg4407.png")
![Graphs of probability P of not observing independent events each of probability 1/n after n Bernoulli trials, and 1 - P vs n ; it can be observed that as n increases, the probability of a 1/n-chance event never appearing after n tries rapidly converges to 1/e.](/Images/godic/202501/12/Bernoulli_trial_sequence.svg4407.png")
![](/Images/godic/202501/12/Exp_derivative_at_0.svg4407.png")
The number e is an important mathematical constant that is the base of the natural logarithm. It is approximately equal to 2.71828, and is the limit of (1 + 1/n) as n approaches infinity, an expression that arises in the study of compound interest. It can also be calculated as the sum of the infinite series