An infinite number.
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.
81 is an odd number between 7 and 350 that has 3 factors other than itself and 1.
The number 27 is an odd number.It is also a composite number, meaning that it factors other than itself and 1.Being an odd number, all of its factors must also be odd numbers.Its factors are 1x27 and 3x9.Because 3x3x3 = 27, then 27 is 3 cubed.
There are 44 positive integers less than 2,010 that have an odd number of factors.
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.
If an odd number has more than two factors then it is a composite number but if it has only two factors then it is a prime number. Although all prime numbers are odd except for 2 many more odd numbers are composite numbers having more than two factors as for example 21 is an odd number whose factors are 1, 3, 7 and 21.
Square numbers have an odd number of factors.
189
Square numbers have an odd number of factors.
Perfect squares have an odd number of factors. There are 31 perfect squares less than 1000.
The most factors any odd number less than 100 has is 6. There are 4 numbers which have 6 factors:45, 63, 75 & 99.
Square numbers have an odd number of factors.