diff --git a/index.js b/index.js
index 87eca89..d5494ff 100644
--- a/index.js
+++ b/index.js
@@ -3,7 +3,7 @@
 exports.Client = Client
 exports.Server = Server
 
-var bn = require('bn.js')
+var BN = require('bn.js')
 var bncode = require('bncode')
 var compact2string = require('compact2string')
 var dgram = require('dgram')
@@ -702,7 +702,7 @@ function toUInt32 (n) {
 
 function toUInt64 (n) {
   if (n > MAX_UINT || typeof n === 'string') {
-    var bytes = bn(n).toArray()
+    var bytes = new BN(n).toArray()
     while (bytes.length < 8) {
       bytes.unshift(0)
     }
diff --git a/package.json b/package.json
index 549fcfe..d18ef2d 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,7 @@
     "querystring": "^0.2.0",
     "run-parallel": "^1.0.0",
     "string2compact": "^1.1.0",
-    "bn.js": "^0.3.1"
+    "bn.js": "^0.4.3"
   },
   "devDependencies": {
     "parse-torrent": "^1.1.0",