In mathematical science there is a set of types of numbers: natural, simple, positive, negative, compound and some other which are learned gradually with assimilation of a school course of mathematics. Special attention should be paid on composite numbers.
The composite number is understood as number which can be divided not only into unit and itself, but also into some other dividers and numbers. Examples of composite numbers are, 4, 8, 24, 39, etc. This row can be continued infinitely. Composite numbers are a version natural.
Natural numbers - all this without number exception after unit which appear by itself at transfer of various objects (for example, on the street of 14 buildings, in city live of 149000 people, etc.). All natural numbers are whole (i.e. those numbers which do not include any shares).
Speaking in other words, all natural numbers are divided into simple and compound. There is the main theorem of arithmetics of prime numbers which meaning is that any is natural and compound. It turns out by the work of the three and the seven. Are 3 and 7 prime numbers. Prime and composite numbers have the interconnected properties: - Let a be a composite number. Then it surely possesses at least one simple divider of n which at its construction in the second degree would be less or is equal to this composite number. For example, number 48 is divided into 3. The three in the second degree becomes the nine, and 9 less than 48. - Let numbers an and b be simple. Then, if they possess the greatest common divisor which will not exceed 1, then these numbers will be called mutually prime. It is, for example, 3 and 7, 11 and 19, etc. - the Work of the greatest common divisor and least common multiple of two prime numbers is always equal to the work of these two numbers. Among all prime numbers stand 0 and 1 alone. It is possible to call unit a prime number only because it turns out by the zero work of quantity of prime numbers.