Check if number is prime number

by 
var number;

Console.WriteLine("Accept number:");
number = Convert.ToInt32(Console.ReadLine());

if (IsPrime(number))
{
    Console.WriteLine("It is prime");
}
else
{
    Console.WriteLine("It is not prime");
}       

public static bool IsPrime(int number)
{
    if (number <= 1) return false;
    if (number == 2) return true;
    if (number % 2 == 0) return false;

    var boundary = (int)Math.Floor(Math.Sqrt(number));
          
    for (int i = 3; i <= boundary; i += 2)
        if (number % i == 0)
            return false;
    
    return true;        
}

I changed number / 2 to Math.Sqrt(number) because from in wikipedia, they said:

This routine consists of dividing n by each integer m that is greater
than 1 and less than or equal to the square root of n. If the result
of any of these divisions is an integer, then n is not a prime,
otherwise it is a prime. Indeed, if n = a*b is composite (with a and b ≠

  1. then one of the factors a or b is necessarily at most square root of n

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