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All prime squares have exactly three factors.49 has exactly three factors: 1, 7, and 49.
A prime number has exactly two factors.
A number has exactly three factors if and only if it is the square of a prime number.
49 has exactly 3 factors (1, 7, and 49) and is greater than 40 and less than 60.
A number that has exactly two (positive) factors is called a prime number. For instance, the only factors of 7 are 1 and 7.
729 is the second number with exactly 7.
There are an infinite number of integers with "only 7 factors". Any number which is the product of exactly 7 prime numbers.
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64 is the least number having exactly 7 factors: 1, 2, 4, 8, 16, 32, and 64.
All prime squares have exactly three factors.49 has exactly three factors: 1, 7, and 49.
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64
Any number that is the 6th power of a prime integer.
Their common factors are 1 and 7 .
It is 2^6 = 64.
A prime number has exactly two factors.