64
80
The largest two-digit multiple of six is 96.
25
9 has three factors: 1, 3, and 9
9409
95
997
The largest one digit number that has three factors is 9. Its factors are 1, 3, and 9.
How about 99 whose factors are: 1, 3, 9, 11 33 and 99
The best way to tackle this is to take the largest 3 digit number (999) and work out its prime factors. You can then work down until you get one with exactly five prime factors. 999 is 3x3x3x37, 998 is 2x499, 997 is prime, 996 is 2x2x3x83, 995 is 5x199, 994 is 2x7x71, 993 is 3x331, 992 is 2x2x2x2x2x31, 991 is prime, 990 is 2x3x3x5x11. That is the first we came across with five prime factors. Therefore the largest 3 digit number with exactly five prime factors is 990.
97
Oh, dude, the largest two-digit number with exactly 7 factors is 48. Yeah, it's like a hidden gem in the world of numbers. It's got 1, 2, 3, 4, 6, 8, and 12 as factors, making it the cool kid with just the right amount of friends.
I think you mean, the largest four digit number that has exactly three divisors. 2X3X1663=9,978
36 has nine factors.
625 has five factors.
64