Euler 21

21.js

var max = 1e4, obj = {}, val = t = i = 0
 
function sum( n ) {
  for ( var m = Math.sqrt(n), v = 1, i = 2; i <= m; ++i )
    !(n % i) && (v += i) && i != m && (v += n / i)
  return n ? v : 0
}
 
for ( ; i < max; ++i )
  if ( !obj[i] && (t = sum(i)) != i && sum(t) == i )
    val += (obj[i] = obj[t] = i + t)
 
console.log(val)

21.py

import math

maximum = 10000
lookup = []
result = 0

def getDivisors ( num ):
  end = int( math.floor( math.sqrt(num) ) )
  val = 1
  for i in range (2, end):
    if num % i == 0:
      val = val + i
      if i * i != num:
        val = val + ( num / i )
  return val

for i in range (0, maximum):
  if i in lookup:
    continue
  temp = getDivisors( i )
  if temp != i and getDivisors( temp ) == i:
    lookup.append(temp)
    lookup.append(i)
    result = result + temp + i

print( result )

Kevins-MacBook-Pro-2:Euler kevin$ time node 21.js
31626

real 0m0.204s
user 0m0.193s
sys 0m0.010s

Kevins-MacBook-Pro-2:Euler kevin$ time python 21.py
31626

real 0m4.651s
user 0m4.639s
sys 0m0.010s

Better way to find divisors...

Kevins-MacBook-Pro-2:Euler kevin$ time node 21.js
31626

real 0m0.069s
user 0m0.059s
sys 0m0.008s

Kevins-MacBook-Pro-2:Euler kevin$ time python 21.py
31626

real 0m0.218s
user 0m0.210s
sys 0m0.007s

And some more optimizations:

Kevins-MacBook-Pro-2:Euler kevin$ time node 21.js
31626

real 0m0.062s
user 0m0.053s
sys 0m0.008s

Kevins-MacBook-Pro-2:Euler kevin$ time python 21.py
31626

real 0m0.155s
user 0m0.146s
sys 0m0.007s