How many two-digit numbers have exactly four factors? For p1 = 2, p2 can be 5, 7, 11…, 47 => 13 numbers are possible.
Which is the smallest 2 digit number having exactly four factors?
25 is the smallest 2 digit number having exactly 4 factors
What is the greatest two digit prime number?
97
97 is: the 25th prime number (the largest two-digit prime number in base 10), following 89 and preceding 101.
What is the largest 2 digit number with only 3 factors?
25 and 49 are the only two digit numbers which will have exactly three factors. This is because a number will have three factor if and only if the number is a square of a prime number. So 25 and 49 are the only two digit numbers with exactly three factors.
How many 2 digit numbers have exactly 3 factors?
This is because a number will have three factor if and only if the number is a square of a prime number. So 25 and 49 are the only two digit numbers with exactly three factors.
Which is the largest number with 9 factors?
As the number of factors is odd, I reckon it’s a square number – because factors usually come in pairs. So, working downwards as you want the largest number: 81. Factors are 1, 81, 3, 27, and 9. So only 5 factors. 64. 1, 64, 2, 32, 4, 16, 8. So only 7 factors.
Which is the smallest number that has 4 factors?
6 is the smallest number that have 4 factors. 1*2*3=6. Factors are 1,2,3,6 0.01, 0.02, 0.03, 0.06 are all factors of 0.06…. likewise 0.0000000000000000006 will have a similar set of factors. So the answer is something just infitesimally larger than 0. What does Google know about me? Gabriel Weinberg, I run a search engine (Duck Duck Go).
How many factors does a prime number have?
Every number greater than 1 has at least two factors; itself and 1, which is true for every prime number. So the third factor without having any more corresponding multiplicant has to be a perfect square. Only perfect sqaures have odd number of factors and all other numbers have even number of factors.
