input.onchange = function(){
const num = input.Value;
if(isNaN(num))
{
para.textContent = 'You need to enter a number';
}
else
{
para.textContent = num + ' square is ' + squared(num) + '. ' +
' cubed is ' + cubed(num) + '. ' +
' factorial is ' + factorial(num);
}
}