It is 69.
99
28
The greatest composite number that is less than 100 is 99. Its factors are 1, 3, 9, 11, 33, and 99. It can't be prime because it has factors other than 1 and itself.
2 is the smallest prime number. 9 is the greatest composite number less than 10. The sum of 2 and 9 is 11.
It is: 2+9 = 11
Any number less than 100 which has more than 2 factors is a composite number
99 = 3 x 3 x 11
4 is a composite number (2 x 2), and it is less than 5.
What is the greatest palindromic number less than 999?
If that's less than 100, the answer is 99.
4 is.