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There are 9 integers less than 100 that have an odd number of factors.
Every factor of a number has a pair, eg 2 & 3 are a factor pair of 6; and so it would be expected that every number has an even number of factors.
However, if the factor pair of a number are the same number (eg 6 & 6 are a factor pair of 36), then there will be an odd number of factors.
When there is a repeated factor like this, the number is a perfect square.
Thus only perfect squares have an odd number of factors.
Less than 100 there are 9 perfect squares (1, 4, 9, 16, 25, 36, 49, 64 & 81) which have an odd number of factors.
100 itself is a perfect square and also has an odd number of factors, but the question asked for those numbers less than 100 with an odd number of factors.
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How many positive integers less than 100 have an odd number of positive divisors?
The squares -- nine of them.
How many numbers which are less than 1000 have an odd number of factors?
Perfect squares have an odd number of factors. There are 31 perfect squares less than 1000.
How many positive integers are there less than 10000?
One less than 10000.
How many positive integers less than or equal to 100 have a prime factor that is greater than 4?
There are 80 such integers.
How many integers are there?
an infinite number. integers are all whole numbers, negative numbers and positive numbers.
How many positive integers less than 2010 have an odd number of factors?
There are 44 positive integers less than 2,010 that have an odd number of factors.
How many integers less than 60 have an even number of factors?
All but the square numbers - 53 of them.
How many positive integers less than 2008 have an even number of divisors?
There are 1,963 such integers. Every factor of a number has a pair. The only time there will be an odd number of factors is if one factor is repeated, ie the number is a perfect square. So the question is really asking: how many positive integers less than 2008 (in the range 1 to 2007) are not perfect squares. √2007 = 44 and a bit (it lies between 44 and 45) So there are 44 integers less than (or equal to) 2007 which are perfect squares → 2007 - 44 = 1963 integers are not perfect squares in the range 1-2007 and have an even number of factors (divisors).
How many positive integers less than 100 have exactly 4 factors?
32
How many positive integers less than 50 have exactly 2 factors?
There are 17.
What are whole number less than 24?
There are infinitely many of them: all integers which are less than 24.
How many positive integers less than 20 have an odd number of distinct factors?
13.1, 2, 3, 4, 5 , 7, 8, 9, 11, 13, 16, 17, and 19.
How many positive integers less than 100 have an odd number of positive divisors?
The squares -- nine of them.
How many integers are less than five?
None. There's no such thing as an interger.There are an infinite number of integers less than five: 4, 3, 2, 1, 0, and all of the negative ones.
Which number less than 20 has the most factors how many are there?
"12" has 6 factors.
How many whole number less than a hundred has the most factors?
the number 90 has the most factors under 100
How many integers less than 1000 are divisible by 11?
There are 90 integers less than 1,000 that are divisible by 11.
