How many divisors of 1350? How many of them are odd?

How many divisors of 1350? How many of them are odd?

1350=2*3*3*3*5*5
The approximate numbers are 1,2,3,5,6,9,10,15,18,25,27,30,45,50,54,75,901351502252704506751350
There are 24
There are 12 odd numbers
This is enumeration
There are also simple ways
1350=2*3*3*3*5*5
So the number is
(1 + 1) (3 + 1) (2 + 1) = 24
Because only one 2 in the factor is even, when the factor A is even, the factor B = 1350 / a must be odd, so the odd number is exactly half, 12

Xiao Ming has 208 pages in a book. He read 48 pages in the first three days. According to this calculation, it will take several days to finish reading

Let Xiao Ming finish it in X days
48:3=208:x
The solution is x = 13 days

How many are there exactly six divisors from 1 to 100? Write the calculation steps

X = A & # 178; B or x = a ^ 52 & # 178; product with Prime Number 3, 5, 7, 11, 13, 17, 19, 23, total 8 3 & # 178; product with prime number 2, 5, 7, 11, total 4 5 & # 178; product with prime number 2, 3, total 2 7 & # 178; product with prime number 2, total 1 5 power of 1 2, total 1: 8 +