text: Tcefrep Numbers | Iterative function to reverse digits of num ; Function to calculate sum of all proper divisors num -- > given natural number ; Final result of summation of divisors ; find all divisors which divides ' num ' ; if ' i ' is divisor of ' num ' ; if both divisors are same then add it only once else add both ; Add 1 to the result as 1 is also a divisor ; Given Number N ; Function Call
code: function reverse ( num ) { let rev_num = 0 ; while ( num > 0 ) { rev_num = rev_num * 10 + num % 10 ; num = parseInt ( num / 10 ) ; } return rev_num ; } function properDivSum ( num ) { let result = 0 ; for ( i = 2 ; i <= Math . sqrt ( num ) ; i ++ ) { if ( num % i == 0 ) { if ( i == ( num / i ) ) result += i ; else result += ( i + num / i ) ; } } return ( result + 1 ) ; } function isTcefrep ( n ) { return properDivSum ( n ) == reverse ( n ) ; } let N = 6 ; if ( isTcefrep ( N ) ) document . write ( " " ) ; else document . write ( " " ) ;