diff --git a/src/blackgui/models/columnformatters.cpp b/src/blackgui/models/columnformatters.cpp
index e074333e6..c2323b30b 100644
--- a/src/blackgui/models/columnformatters.cpp
+++ b/src/blackgui/models/columnformatters.cpp
@@ -186,10 +186,9 @@ namespace BlackGui
                 QTime t = dateTime.value<QTime>();
                 return t.toString(m_formatString);
             }
-            else if (static_cast<QMetaType::Type>(dateTime.type()) == QMetaType::Int)
+            else if (dateTime.isIntegral())
             {
-                //! \todo potential risk if int is not qint64
-                QDateTime t = QDateTime::fromMSecsSinceEpoch(dateTime.toInt());
+                QDateTime t = QDateTime::fromMSecsSinceEpoch(dateTime.value<qint64>());
                 return t.toString(m_formatString);
             }
             else
diff --git a/src/blackmisc/variant.cpp b/src/blackmisc/variant.cpp
index 8844d2c6c..5ccfc8196 100644
--- a/src/blackmisc/variant.cpp
+++ b/src/blackmisc/variant.cpp
@@ -37,6 +37,23 @@ namespace BlackMisc
         return m_v.toString();
     }
 
+    bool CVariant::isIntegral() const
+    {
+        switch (type())
+        {
+        case QMetaType::Bool: case QMetaType::Char: case QMetaType::UChar: case QMetaType::SChar: case QMetaType::Short: case QMetaType::UShort:
+        case QMetaType::Int: case QMetaType::UInt: case QMetaType::Long: case QMetaType::ULong: case QMetaType::LongLong: case QMetaType::ULongLong:
+            return true;
+        default:
+            return false;
+        }
+    }
+
+    bool CVariant::isArithmetic() const
+    {
+        return isIntegral() || type() == QMetaType::Float || type() == QMetaType::Double;
+    }
+
     int CVariant::compareImpl(const CVariant &a, const CVariant &b)
     {
         if (a.userType() < b.userType()) { return -1; }
diff --git a/src/blackmisc/variant.h b/src/blackmisc/variant.h
index 741eeb2d3..fed2ebc56 100644
--- a/src/blackmisc/variant.h
+++ b/src/blackmisc/variant.h
@@ -231,6 +231,12 @@ namespace BlackMisc
         //! \copydoc CValueObject::convertToQString
         QString convertToQString(bool i18n = false) const;
 
+        //! True if this variant's type is an integral type.
+        bool isIntegral() const;
+
+        //! True if this variant's type is an integral or floating-point type.
+        bool isArithmetic() const;
+
         //! Convert this variant to a bool.
         bool toBool() const { return m_v.toBool(); }