Euler's Totient Calculator
Calculate Euler's totient function phi(n) — the count of integers from 1 to n that are coprime to n.
Inputs
Results
phi(n)
4
Coprime Count4
phi(n)/n Ratio0.3333
How to Use This Calculator
- Enter n.
- Review the phi(n) result.
- Use Coprime Count and phi(n)/n Ratio to inform your decision.
- Use the chart to visualize the results and explore different scenarios by adjusting inputs.
How the result changes with n
| n | phi(n) |
|---|---|
| 100,001 | 90,900 |
| 350,001 | 223,776 |
| 650,000 | 240,000 |
| 900,000 | 240,000 |
What each input means
- n
- Positive integer to compute phi(n) for
How this is calculated
Worked example, using the default values
- Identify Input Parametersn = 12 = 1 input(s) provided
- Calculate phiphi4 = 4
- Calculate Coprime CountCoprime Count4 = 4
Engine last updated . Checked against 4 independently-derived tests — how we verify calculators.
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