899.
4 is a composite number (2 x 2), and it is less than 5.
99 is the largest composite number less than 100: its prime factorisation is 3 x 3 x 11
6
398?
598
It is: 299 which has more than 2 factors
47 - 12 = 35
The largest single digit composite number is 9. The largest prime number is 17 million digits long. The definition of a composite number is any number that has at least one positive divisor other than one or the number itself (it is not a prime number). The largest composite digit is therefore longer than the largest prime number by at leaf +1.
39
39
49
4 is.