internal class Program
{
static void Main(string[] args)
{
int exponent = 1;
int number = 2;
int counter = number;
int randMin = 2;
int randMax = 1001;

Random random = new Random();
int numberMax = random.Next(randMin, randMax);

while (counter < numberMax)
{
counter *= number;
exponent++;
}

Console.WriteLine($"Минимальная степень числа {number}, превосходящая число {numberMax} - {exponent}");
Console.ReadKey();
}
}