diff --git a/include/boost/multiprecision/mpfi.hpp b/include/boost/multiprecision/mpfi.hpp
index b863e313..a06e4a39 100644
--- a/include/boost/multiprecision/mpfi.hpp
+++ b/include/boost/multiprecision/mpfi.hpp
@@ -1042,7 +1042,7 @@ inline std::size_t hash_value(const mpfi_float_backend<Digits10>& val)
    std::size_t len = val.left_data()[0]._mpfr_prec / mp_bits_per_limb;
    if(val.left_data()[0]._mpfr_prec % mp_bits_per_limb)
       ++len;
-   for(int i = 0; i < len; ++i)
+   for(std::size_t i = 0; i < len; ++i)
       boost::hash_combine(result, val.left_data()[0]._mpfr_d[i]);
    boost::hash_combine(result, val.left_data()[0]._mpfr_exp);
    boost::hash_combine(result, val.left_data()[0]._mpfr_sign);
@@ -1050,7 +1050,7 @@ inline std::size_t hash_value(const mpfi_float_backend<Digits10>& val)
    len = val.right_data()[0]._mpfr_prec / mp_bits_per_limb;
    if(val.right_data()[0]._mpfr_prec % mp_bits_per_limb)
       ++len;
-   for(int i = 0; i < len; ++i)
+   for(std::size_t i = 0; i < len; ++i)
       boost::hash_combine(result, val.right_data()[0]._mpfr_d[i]);
    boost::hash_combine(result, val.right_data()[0]._mpfr_exp);
    boost::hash_combine(result, val.right_data()[0]._mpfr_sign);
@@ -1420,7 +1420,7 @@ struct constant_pi<boost::multiprecision::number<boost::multiprecision::mpfi_flo
 {
    typedef boost::multiprecision::number<boost::multiprecision::mpfi_float_backend<Digits10>, ExpressionTemplates> result_type;
    template<int N>
-   static inline result_type const& get(const mpl::int_<N>&)
+   static inline const result_type& get(const mpl::int_<N>&)
    {
       mpfi_initializer<result_type>::force_instantiate();
       static result_type result;
@@ -1444,7 +1444,7 @@ struct constant_ln_two<boost::multiprecision::number<boost::multiprecision::mpfi
 {
    typedef boost::multiprecision::number<boost::multiprecision::mpfi_float_backend<Digits10>, ExpressionTemplates> result_type;
    template<int N>
-   static inline result_type get(const mpl::int_<N>&)
+   static inline const result_type& get(const mpl::int_<N>&)
    {
       mpfi_initializer<result_type>::force_instantiate();
       static result_type result;
diff --git a/include/boost/multiprecision/mpfr.hpp b/include/boost/multiprecision/mpfr.hpp
index f6f9a625..2759a8a8 100644
--- a/include/boost/multiprecision/mpfr.hpp
+++ b/include/boost/multiprecision/mpfr.hpp
@@ -1517,7 +1517,7 @@ inline std::size_t hash_value(const mpfr_float_backend<Digits10, AllocateType>&
    std::size_t len = val.data()[0]._mpfr_prec / mp_bits_per_limb;
    if(val.data()[0]._mpfr_prec % mp_bits_per_limb)
       ++len;
-   for(int i = 0; i < len; ++i)
+   for(std::size_t i = 0; i < len; ++i)
       boost::hash_combine(result, val.data()[0]._mpfr_d[i]);
    boost::hash_combine(result, val.data()[0]._mpfr_exp);
    boost::hash_combine(result, val.data()[0]._mpfr_sign);
diff --git a/include/boost/multiprecision/number.hpp b/include/boost/multiprecision/number.hpp
index b841b7fb..c3819dc5 100644
--- a/include/boost/multiprecision/number.hpp
+++ b/include/boost/multiprecision/number.hpp
@@ -1856,78 +1856,6 @@ inline std::istream& operator >> (std::istream& is, rational<multiprecision::num
    return is;
 }
 
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator == (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a == multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator == (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a == multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator != (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a != multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator != (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a != multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator < (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a < multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator < (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a > multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator <= (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a <= multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator <= (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a >= multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator > (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a > multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator > (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a < multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator >= (const rational<multiprecision::number<T, ExpressionTemplates> >& a, const Arithmetic& b)
-{
-   return a >= multiprecision::number<T, ExpressionTemplates>(b);
-}
-
-template <class T, multiprecision::expression_template_option ExpressionTemplates, class Arithmetic>
-typename boost::enable_if<boost::is_arithmetic<Arithmetic>, bool>::type operator >= (const Arithmetic& b, const rational<multiprecision::number<T, ExpressionTemplates> >& a)
-{
-   return a <= multiprecision::number<T, ExpressionTemplates>(b);
-}
-
 template <class T, multiprecision::expression_template_option ExpressionTemplates>
 inline multiprecision::number<T, ExpressionTemplates> numerator(const rational<multiprecision::number<T, ExpressionTemplates> >& a)
 {