The number of generators of a cyclic group of order 'n' is the number of elements less than n but greater than or equal to 1, which are also coprime to n.

Here, n=5.

So all the numbers less than 5 but greater than equal to 1, which are also coprime (HCF of 5 and that number is 1) to 5 are: 1, 2, 3, 4.

That is, 4 numbers. So the number of generators of cyclic group of order 5 is 4.