function integer_to_roman(num) {  
    if (typeof num !== 'number')   
    return false;   
      
    var digits = String(+num).split(""),  
    key = ["","C","CC","CCC","CD","D","DC","DCC","DCCC","CM",  
    "","X","XX","XXX","XL","L","LX","LXX","LXXX","XC",  
    "","I","II","III","IV","V","VI","VII","VIII","IX"],  
    roman_num = "",  
    i = 3;  
    while (i--)  
    roman_num = (key[+digits.pop() + (i * 10)] || "") + roman_num;  
    return Array(+digits.join("") + 1).join("M") + roman_num;  
    }  
      
    console.log(integer_to_roman(27));