The number 2 only has two factors, as 2 = 1 x 2 and 2 is a prime number, which means that its only factors are 1 and itself.
Every non-zero integer (besides 1) has at least two factors: 1 and itself. We also know that 4 is an even number, which means that it is divisible by 2. So, the factors of 4 are 1, 2, 4. There are no other numbers that divide evenly into 4.