diff --git a/NewKernel_d/include/CGAL/NewKernel_d/utils.h b/NewKernel_d/include/CGAL/NewKernel_d/utils.h
index fb661f5397e..adc632e50c6 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/utils.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/utils.h
@@ -88,7 +88,7 @@ struct Has_type_different_from <T, No, true>
                 }
         };
 
-        template <class NT> struct has_cheap_constructor : boost::is_arithmetic<NT>{};
+        template <class NT> struct has_cheap_constructor : std::is_arithmetic<NT>{};
         template <bool p> struct has_cheap_constructor<Interval_nt<p> > {
                         enum { value=true };
         };
diff --git a/Number_types/include/CGAL/Lazy_exact_nt.h b/Number_types/include/CGAL/Lazy_exact_nt.h
index 38c55c62d32..6890fc17420 100644
--- a/Number_types/include/CGAL/Lazy_exact_nt.h
+++ b/Number_types/include/CGAL/Lazy_exact_nt.h
@@ -18,7 +18,6 @@
 
 #include <CGAL/boost/iterator/transform_iterator.hpp> // for Root_of functor
 #include <boost/operators.hpp>
-#include <boost/type_traits/is_arithmetic.hpp>
 
 #include <boost/mpl/if.hpp>
 #include <boost/mpl/logical.hpp>
@@ -383,7 +382,7 @@ public :
   // Also check that ET and AT are constructible from T?
   template<class T>
   Lazy_exact_nt (T i, std::enable_if_t<boost::mpl::and_<
-      boost::mpl::or_<boost::is_arithmetic<T>, std::is_enum<T> >,
+      boost::mpl::or_<std::is_arithmetic<T>, std::is_enum<T> >,
       boost::mpl::not_<std::is_same<T,ET> > >::value,void*> = 0)
     : Base(new Lazy_exact_Cst<ET,T>(i)) {}