1. The problem is to understand the number 4 and its properties. 2. The number 4 is a positive integer and an even number. 3. It is the square of 2, since $4 = 2^2$. 4. It is also the smallest composite number, having divisors 1, 2, and 4. 5. In algebra, 4 can be used as a constant or coefficient in expressions and equations. 6. For example, in the equation $y = 4x$, 4 is the slope of the line. 7. Understanding the number 4 helps in various mathematical contexts such as counting, measurement, and algebraic operations. Final answer: The number is 4, an even, composite number and the square of 2.