If factors include 1 and the number itself then the any number (n) with only 4 factors has to be the product of two prime numbers, p1 and p2. The factors are then n, p1, p2, and 1. The largest 3-digit number with only 4 factors is 998. The factors are 998, 499, 2 and 1
Three is a prime number so its only divisors (factors) are 1 and itself.
The way to be sure you have one of these is to take any three distinct prime numbers and multiply them. Those three prime numbers are then the only factors the product can have. An example is the number 30, which has factors of 2, 3 and 5.
A number that has only two factors is called a prime. The only factors of a prime are 1 and the number itself.
For a number to have [only] 2 factors, it must be a prime number; the prime numbers between 0 and 20 are; 2, 3, 5, 7, 11, 13, 17, 19
25
25
Square numbers have an odd number of factors. Other numbers have an even number of factors. The squares between 12 and 40 include 16, 25, and 36. If the number has only three factors, it must be the square of a prime number, since two of the factors will be 1 and itself, so if there is only one more factor, this third number cannot have factors itself. This means the number must be 25, whose factors are 1, 5, and 25. Response: 24 has (at least) three factors - 1, 2, 3, 4, 6, 8, 12, and 24 .
A square number
Well, the factors of a prime number is that they only have two factors.
The numbers with only three factors are squares of prime numbers.
Okay, whoever said that a number can only have an even number of factors IS Wrong Take a prime number and square it. If you square a prime number, the number you get will only have 3 factors. For example, if I squared the number 3, I would get 9. 9 only has three factors: 9, 3, 1 Any prime number squared has Three factors.
3 is a prime number; its only factors are 1 and itself.
A number has exactly three factors if and only if it is the square of a prime number.
Squares of prime numbers are the only numbers with three factors, since there must be only one nontrivial divisor for a number to have three factors. That number must thus be prime.
1 is the only number between 1 and 100 that has too few factors to be a prime number.
17 If the number has only two factors, it must be a prime number. The only factors of 17 are 1 and 17. The difference between 1 and 17 is 16.