Prime numbers, also known as prime numbers, have an infinite number of them. One greater than 1 Nature number, in addition to 1 and itself, can not be divided by other Nature number (except 0) number called Prime numbers); otherwise known as the combined number. According to the Fundamental Theorem of Arithmetic, each one is larger than 1 integer, either itself is one prime number, or can be written as a series of prime number product; and does not take into account the order of these primes in the product, then write out formality is unique.

In the Nature number field, primes are irreducible, and are the basic elemental component of all Nature numbers. For example, 10 is the product of 2's and 5's. There are an infinite number of primes, so there are an infinite number of elementals in the arithmetic world. All objects, theorems, and methods in the arithmetic world, both are composed of their basic elemental primes.