diff --git a/Src/Newtonsoft.Json.Tests/Converters/XmlNodeConverterTest.cs b/Src/Newtonsoft.Json.Tests/Converters/XmlNodeConverterTest.cs
index 8df81e94..58d87a54 100644
--- a/Src/Newtonsoft.Json.Tests/Converters/XmlNodeConverterTest.cs
+++ b/Src/Newtonsoft.Json.Tests/Converters/XmlNodeConverterTest.cs
@@ -2338,6 +2338,22 @@ namespace Newtonsoft.Json.Tests.Converters
 
             Assert.AreEqual(@"<root><b xmlns=""http://www.example.com/ns"">Asd</b><c>AAA</c><test>adad</test></root>", xmlBack.OuterXml);
         }
+
+#if !(NET20 || NET35 || PORTABLE || PORTABLE40)
+        [Test]
+        public void DeserializeBigInteger()
+        {
+            var json = "{\"DocumentId\":13779965364495889899 }";
+
+            XmlDocument node = JsonConvert.DeserializeXmlNode(json);
+
+            Assert.AreEqual("<DocumentId>13779965364495889899</DocumentId>", node.OuterXml);
+
+            string json2 = JsonConvert.SerializeXmlNode(node);
+
+            Assert.AreEqual(@"{""DocumentId"":""13779965364495889899""}", json2);
+        }
+#endif
     }
 }
 #endif
\ No newline at end of file
diff --git a/Src/Newtonsoft.Json.Tests/Serialization/ExtensionDataTests.cs b/Src/Newtonsoft.Json.Tests/Serialization/ExtensionDataTests.cs
index 4da7c9a2..512e07e7 100644
--- a/Src/Newtonsoft.Json.Tests/Serialization/ExtensionDataTests.cs
+++ b/Src/Newtonsoft.Json.Tests/Serialization/ExtensionDataTests.cs
@@ -48,7 +48,7 @@ namespace Newtonsoft.Json.Tests.Serialization
         public class CustomDictionary : IDictionary<string, object>
         {
             private readonly IDictionary<string, object> _inner = new Dictionary<string, object>();
- 
+
             public void Add(string key, object value)
             {
                 _inner.Add(key, value);
@@ -235,7 +235,7 @@ namespace Newtonsoft.Json.Tests.Serialization
         }
 
 #pragma warning disable 649
-        class ExtendedObject
+        private class ExtendedObject
         {
             [JsonExtensionData]
             internal IDictionary<string, JToken> _additionalData;
@@ -744,5 +744,90 @@ namespace Newtonsoft.Json.Tests.Serialization
             Assert.AreEqual(1, c.CustomFields.Count);
             Assert.AreEqual("Testing", (string)c.CustomFields["CustomField1"]);
         }
+
+        public class DocNoSetter
+        {
+            private readonly JObject _content;
+
+            public DocNoSetter()
+            {
+            }
+
+            public DocNoSetter(JObject content)
+            {
+                _content = content;
+            }
+
+            [JsonProperty("_name")]
+            public string Name { get; set; }
+
+            [JsonExtensionData]
+            public JObject Content
+            {
+                get { return _content; }
+            }
+        }
+
+        [Test]
+        public void SerializeExtensionData_NoSetter()
+        {
+            string json = JsonConvert.SerializeObject(new DocNoSetter(new JObject(new JProperty("Property1", 123)))
+            {
+                Name = "documentName"
+            });
+            Assert.AreEqual(@"{""_name"":""documentName"",""Property1"":123}", json);
+        }
+
+        [Test]
+        public void SerializeExtensionData_NoSetterAndNoValue()
+        {
+            string json = JsonConvert.SerializeObject(new DocNoSetter(null)
+            {
+                Name = "documentName"
+            });
+            Assert.AreEqual(@"{""_name"":""documentName""}", json);
+        }
+
+        [Test]
+        public void DeserializeExtensionData_NoSetterAndNoExtensionData()
+        {
+            DocNoSetter doc = JsonConvert.DeserializeObject<DocNoSetter>(@"{""_name"":""documentName""}");
+
+            Assert.AreEqual("documentName", doc.Name);
+        }
+
+        [Test]
+        public void DeserializeExtensionData_NoSetterAndWithExtensionData()
+        {
+            try
+            {
+                JsonConvert.DeserializeObject<DocNoSetter>(@"{""_name"":""documentName"",""Property1"":123}");
+            }
+            catch (JsonSerializationException ex)
+            {
+                Assert.AreEqual("Error setting value in extension data for type 'Newtonsoft.Json.Tests.Serialization.ExtensionDataTests+DocNoSetter'. Path 'Property1', line 1, position 39.", ex.Message);
+                Assert.AreEqual("Cannot set value onto extension data member 'Content'. The extension data collection is null and it cannot be set.", ex.InnerException.Message);
+            }
+        }
+
+        public class DocNoGetter
+        {
+            [JsonExtensionData]
+            public JObject Content
+            {
+                set { }
+            }
+        }
+
+        [Test]
+        public void SerializeExtensionData_NoGetter()
+        {
+            ExceptionAssert.Throws<JsonException>(
+                () =>
+                {
+                    JsonConvert.SerializeObject(new DocNoGetter());
+                },
+                "Invalid extension data attribute on 'Newtonsoft.Json.Tests.Serialization.ExtensionDataTests+DocNoGetter'. Member 'Content' must have a getter.");
+        }
     }
 }
\ No newline at end of file
diff --git a/Src/Newtonsoft.Json/Converters/XmlNodeConverter.cs b/Src/Newtonsoft.Json/Converters/XmlNodeConverter.cs
index 9607d6a0..aa47cffa 100644
--- a/Src/Newtonsoft.Json/Converters/XmlNodeConverter.cs
+++ b/Src/Newtonsoft.Json/Converters/XmlNodeConverter.cs
@@ -23,6 +23,7 @@
 // OTHER DEALINGS IN THE SOFTWARE.
 #endregion
 
+using System.Numerics;
 #if !PORTABLE40
 using System;
 using System.Collections.Generic;
@@ -1417,6 +1418,11 @@ namespace Newtonsoft.Json.Converters
             }
             else if (reader.TokenType == JsonToken.Integer)
             {
+#if !(NET20 || NET35 || PORTABLE || PORTABLE40)
+                if (reader.Value is BigInteger)
+                    return ((BigInteger)reader.Value).ToString(CultureInfo.InvariantCulture);
+#endif
+
                 return XmlConvert.ToString(Convert.ToInt64(reader.Value, CultureInfo.InvariantCulture));
             }
             else if (reader.TokenType == JsonToken.Float)
diff --git a/Src/Newtonsoft.Json/Serialization/DefaultContractResolver.cs b/Src/Newtonsoft.Json/Serialization/DefaultContractResolver.cs
index 797bfa52..7a67ecc6 100644
--- a/Src/Newtonsoft.Json/Serialization/DefaultContractResolver.cs
+++ b/Src/Newtonsoft.Json/Serialization/DefaultContractResolver.cs
@@ -25,6 +25,7 @@
 
 using System;
 using System.Collections;
+using Newtonsoft.Json.Schema;
 #if !(NET35 || NET20 || PORTABLE || PORTABLE40)
 using System.Collections.Concurrent;
 #endif
@@ -438,6 +439,9 @@ namespace Newtonsoft.Json.Serialization
                 if (!m.IsDefined(typeof(JsonExtensionDataAttribute), false))
                     return false;
 
+                if (!ReflectionUtils.CanReadMemberValue(m, true))
+                    throw new JsonException("Invalid extension data attribute on '{0}'. Member '{1}' must have a getter.".FormatWith(CultureInfo.InvariantCulture, GetClrTypeFullName(m.DeclaringType), m.Name));
+
                 Type t = ReflectionUtils.GetMemberUnderlyingType(m);
 
                 Type dictionaryType;
@@ -479,10 +483,12 @@ namespace Newtonsoft.Json.Serialization
             else
                 createdType = t;
 
-            MethodInfo addMethod = t.GetMethod("Add", new[] { keyType, valueType });
             Func<object, object> getExtensionDataDictionary = JsonTypeReflector.ReflectionDelegateFactory.CreateGet<object>(member);
-            Action<object, object> setExtensionDataDictionary = JsonTypeReflector.ReflectionDelegateFactory.CreateSet<object>(member);
+            Action<object, object> setExtensionDataDictionary = (ReflectionUtils.CanSetMemberValue(member, true, false))
+                ? JsonTypeReflector.ReflectionDelegateFactory.CreateSet<object>(member)
+                : null;
             Func<object> createExtensionDataDictionary = JsonTypeReflector.ReflectionDelegateFactory.CreateDefaultConstructor<object>(createdType);
+            MethodInfo addMethod = t.GetMethod("Add", new[] { keyType, valueType });
             MethodCall<object, object> setExtensionDataDictionaryValue = JsonTypeReflector.ReflectionDelegateFactory.CreateMethodCall<object>(addMethod);
 
             ExtensionDataSetter extensionDataSetter = (o, key, value) =>
@@ -490,6 +496,9 @@ namespace Newtonsoft.Json.Serialization
                 object dictionary = getExtensionDataDictionary(o);
                 if (dictionary == null)
                 {
+                    if (setExtensionDataDictionary == null)
+                        throw new JsonSerializationException("Cannot set value onto extension data member '{0}'. The extension data collection is null and it cannot be set.".FormatWith(CultureInfo.InvariantCulture, member.Name));
+
                     dictionary = createExtensionDataDictionary();
                     setExtensionDataDictionary(o, dictionary);
                 }