16
A prime number has exactly two factors: itself and 1.
Square numbers have an odd number of factors.
Prime numbers like 2, 3, 5 and 7
The factors of 4 are 1, 2, and 4. The only prime factor of 4 is 2. The factors of 20 are 1, 2, 4, 5, 10, and 20. The prime factors of 20 are 2x2x5.
16 and 81 have 5 factors
625 has five factors.
The numbers between 10 and 30 that have exactly 5 factors are 16 and 25. The number 16 has factors 1, 2, 4, 8, and 16. The number 25 has factors 1, 5, 25, but since it is a perfect square, it also includes the repeated factor of 5. These are the only two numbers between 10 and 30 that have exactly 5 factors.
625 has five factors.16 does, among others.
Indeed, the number 16 has 5 factors, 1, 2, 4, 8, and 16.
A prime number, like 2, 3 or 5.
16
16 does.
16
16
A prime number has exactly two factors.
A number with exactly five factors is a number that is a prime number raised to the fourth power (p4). The factors are 1, p, p2, p3, and p4. Examples: The 5 factors of 24 = 16 are 1, 2, 4, 8, and 16. The 5 factors of 34 = 81 are 1, 3, 9, 27, and 81. The 5 factors of 54 = 625 are 1, 5, 25, 125, and 625.