The multiples of 441 (which are infinite) are all divisible by 441, including these: 441, 882, 1323, 1764, 2205, 2646, 3087, 3528, 3969 . . .
All multiples of 147 are divisible by 147: 147, 294, 441, 588, 735, ...
no
Yes, 3 × 147 = 441
Yes but it will have a remainder because 5 is not a factor of 441
1, 3, 7, 9, 21, 49, 63, 147, 441
Yes but it will have a remainder of 1
No, prime numbers refer to whole numbers, not decimals.
All numbers are divisible by 1.
21 multiplies to 21 to make it 441
1764
3*3*7*7 = 441
2 + 3 + 5 + 431 = 441