No.
yes
1,3,5,9,15,17,45,51,85,153,255,765
Yes
No. A number that ends in 5 is divisible by 5, so it can't be prime unless it is 5 itself. Also, 7+6+5 = 18. Since 18 is divisible by 3 and by 9, 765 is also divisible by 3 and 9. It is easily seen that 765 factorises to 3 x 3 x 5 x17.
Composite. Is divisible by 5
765 divided by 6 is 127.5
Yes. 3,060 divided by 4 is 765.
The numbers that are divisible by 255 are infinite. They include: 255, 510, 765, 1020, 1275, 1530, 1785 . . .
Composite, since it is divisible by 5. ■
Yes, you get a quotient of 255 which is a whole number and with no remainders.
6 is not divisible by 162. 162 is divisible by 6.
For this and any question like it but with a different number, infinity. Numbers never end.