Question 1

What is a prime number?

Accepted Answer

A number divisible only by 1 and itself. Primes: 2,3,5,7,11,13,17,19,23... 2 is the only even prime.

Question 2

Is 1 a prime number?

Accepted Answer

No. 1 is neither prime nor composite. By definition, primes have exactly two distinct divisors (1 and themselves).

Question 3

How accurate are these calculations?

Accepted Answer

Our calculator uses double-precision floating-point arithmetic, accurate to about 15-16 significant digits for most calculations.

Question 4

Can I use the result in further calculations?

Accepted Answer

Yes, results are calculated to full precision. You can copy the exact value or use the rounded display depending on your needs.

Prime Number Checker Calculator - Free Online

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