If a number has 5 factors then it most certainly is not prime. Hence there is some confusion as to what you are asking here.
154
Just multiply the first three prime numbers together.
Just multiply the two smallest prime numbers. That's your number.
2 and 3 are the smallest prime numbers. So answer is 2^3 * 3^3 = 216
6
The smallest prime factors are 2,3,5,7 thus the smallest number would be the product of these will be 210
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).
How about: 105
1155
30,030 Factorization: 2x3x5x7x11x13
5 and 11
Oh, dude, the smallest number with 4 different prime factors is 2 x 3 x 5 x 7, which equals 210. It's like the VIP of numbers, all exclusive with its different prime factor squad. So yeah, that's the answer, no biggie.
36
154
The smallest number with three different prime factors is 30.
Just multiply the first three prime numbers together.
70 is the smallest number that has prime factors of 2,5 and 7