Its...........60!
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The factors of 3 are 1 and 3.The factors of 4 are 1, 2, and 4.The factors of 5 are 1 and 5.The only common factor of 3, 4, and 5 is 1. The least common factor is 1.
The least common multiple, or LCM, of 1, 2, 3, 4 and 5 is 60.
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45 has six factors.
3*5*7*9 = 945 ...check if any number less than that has exactly four distinct factors.
2310 = 2 * 3 * 5 * 7 * 11
Logically, the smallest number with 4 different prime factors would have to be the product of the smallest four prime numbers. So the smallest natural number with four different prime factors is 210 (2*3*5*7).
295 is not a prime number because it has a factor of 5, while prime numbers only have factors of itself and 1. 295 can be divded by 5, giving it at least 4 factors, and thus disqualifies it from fitting the definiton of a prime number.
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