Any square of the infinitely many odd numbers!
Even square numbers are even, by definition. Two even numbers multiplied together give an even number so no, they cannot multiply to give an odd number. You have to multiply an even number by an odd number to do this.
No, only square numbers have an odd number of factors.
The square of every positive or negative even whole number is a positive even whole number. The square of every positive or negative odd whole number is a positive odd whole number. There are an infinite number of each kind.
A square number is a number that is the result of multiplying an integer by itself. For example, 1, 4, 9, 16, and 25 are square numbers because they are the result of 1x1, 2x2, 3x3, 4x4, and 5x5 respectively. While square numbers can be odd or even, they are always whole numbers.
No. Perfect square numbers have an odd number of factors.
Not necessarily. Square numbers don't.
Any even exponent of 3 is a square number.
The factors of all numbers can be written in pairs. With square numbers, one of those pairs is the same number twice. When listed singly, square numbers have an odd number of factors. All others are even.
No, but only in the case of the number 1 (12=1) are square numbers odd.
Even powers of prime numbers. Square numbers have an odd number of factors.
No, square numbers have an odd number of factors.
Square numbers have an odd number of factors, all others have an even number. In this context, primes can either be considered as having 0 factors (an even number) or 2 factors - 1 and itself, again, an even number.