diff --git a/lib/mathlib.cpp b/lib/mathlib.cpp
index 2e2fe2f43..a626b51e8 100644
--- a/lib/mathlib.cpp
+++ b/lib/mathlib.cpp
@@ -528,7 +528,14 @@ MathLib::bigint MathLib::toLongNumber(const std::string & str)
         return characterLiteralToLongNumber(str.substr(1,str.size()-2));
     }
 
-    bigint ret = 0;
+    if (str[0] == '-') {
+        bigint ret = 0;
+        std::istringstream istr(str);
+        istr >> ret;
+        return ret;
+    }
+
+    biguint ret = 0;
     std::istringstream istr(str);
     istr >> ret;
     return ret;
diff --git a/lib/token.cpp b/lib/token.cpp
index fb13e346c..fe1f6c8c4 100644
--- a/lib/token.cpp
+++ b/lib/token.cpp
@@ -1355,7 +1355,10 @@ void Token::printValueFlow(bool xml, std::ostream &out) const
                 out << "      <value ";
                 switch (it->valueType) {
                 case ValueFlow::Value::INT:
-                    out << "intvalue=\"" << it->intvalue << '\"';
+                    if (tok->valueType() && tok->valueType()->sign == ValueType::UNSIGNED)
+                        out << "intvalue=\"" << (MathLib::biguint)it->intvalue << '\"';
+                    else
+                        out << "intvalue=\"" << it->intvalue << '\"';
                     break;
                 case ValueFlow::Value::TOK:
                     out << "tokvalue=\"" << it->tokvalue << '\"';
@@ -1384,7 +1387,10 @@ void Token::printValueFlow(bool xml, std::ostream &out) const
                     out << ",";
                 switch (it->valueType) {
                 case ValueFlow::Value::INT:
-                    out << it->intvalue;
+                    if (tok->valueType() && tok->valueType()->sign == ValueType::UNSIGNED)
+                        out << (MathLib::biguint)it->intvalue;
+                    else
+                        out << it->intvalue;
                     break;
                 case ValueFlow::Value::TOK:
                     out << it->tokvalue->str();
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index f0687a956..7751b11c9 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -242,6 +242,7 @@ private:
         ASSERT_EQUALS(0, valueOfTok("x(NULL);", "NULL").intvalue);
         ASSERT_EQUALS((int)('a'), valueOfTok("x='a';", "'a'").intvalue);
         ASSERT_EQUALS((int)('\n'), valueOfTok("x='\\n';", "'\\n'").intvalue);
+        ASSERT_EQUALS(18446744069414584320, valueOfTok("x=0xFFFFFFFF00000000;","18446744069414584320U").intvalue); // #7701
     }
 
     void valueFlowString() {