@dxzmpk/js-algorithms-data-structures
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Algorithms and data-structures implemented on JavaScript
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# Primality Test
A **prime number** (or a **prime**) is a natural number greater than `1` that
cannot be formed by multiplying two smaller natural numbers. A natural number
greater than `1` that is not prime is called a composite number. For
example, `5` is prime because the only ways of writing it as a
product, `1 × 5` or `5 × 1`, involve `5` itself. However, `6` is
composite because it is the product of two numbers `(2 × 3)` that are
both smaller than `6`.
A **primality test** is an algorithm for determining whether an input
number is prime. Among other fields of mathematics, it is used
for cryptography. Unlike integer factorization, primality tests
do not generally give prime factors, only stating whether the
input number is prime or not. Factorization is thought to be
a computationally difficult problem, whereas primality testing
is comparatively easy (its running time is polynomial in the
size of the input).
## References
- [Prime Numbers on Wikipedia](https://en.wikipedia.org/wiki/Prime_number)
- [Primality Test on Wikipedia](https://en.wikipedia.org/wiki/Primality_test)