Perfect squares have an odd number of factors. There are 31 perfect squares less than 1000.
Literally every single even number less than 1000 is a composite number other than 2 which is prime.
Every second number greater than 2 is an even number.
512 = 29 or 768 = 28*3 have 9 prime factors each.
By definition, a prime number has exactly two factors. So, there are no prime numbers with exactly three factors.
Four of them.
There are 31 numbers less than 1,000 which have an odd number of factors. They are: 1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,256,289,324,361,400,441,484,529,576,625,676,729,784,841,900,961.
210 has 4, which is the maximum possible. There are other numbers with 4 different prime factors.
1000 more is 577233 1000 less is 575233
11
577233 and 575233 respectively
840
There are 12 numbers less than 150 which have an odd number of factors: 1,4,9,16,25,36,49,64,81,100,121,144.
Oh, dude, that's an easy one. So, you can write any number less than 1000 as the product of 3 consecutive numbers, right? Well, except for the numbers at the beginning and end because they don't have 3 numbers before or after them to multiply with. So, that leaves us with 997 numbers. Easy peasy lemon squeezy.
There are four odd numbers less that 100 that have 6 factor. This does not compare with even numbers that have 12 factors!
If you take away 1000 from 503000019 you get 502999019.If you add 1000 to 503000019 you get 503001019.
Literally every single even number less than 1000 is a composite number other than 2 which is prime.
The three greatest whole numbers less than 200 that each have an odd number of factors are 144, 169 and 196.