The venn diagram shows three types of numbers: odd (o), even (e), and prime (p). which is represented by ø?

Odd(O)= {.....-101,.......-1,......3,5,.......1001......}

Even(E)=  {......-1000,.......-500,.....-100,.....-2,0,.....10,...20,....200,....20000....}

Prime (P)=  { .........-1001,-401,...-201,.....-97,....-3,-2,.....2,3,5,7.....101,.....}

Now the set Ф = {set having no element}= Neither odd nor even nor prime.

                        = All the numbers in the number system is either odd or even

                       = Number Ф[ No number has been invented till yet]

As you have not shown the venn diagram, 2 is a prime number which is even , 3 is a prime number which is odd .