diff --git a/src/code.jl b/src/code.jl
index 8b1953b20..774c26931 100644
--- a/src/code.jl
+++ b/src/code.jl
@@ -140,18 +140,18 @@ end
 
 function function_to_expr(op::typeof(^), O, st)
     args = arguments(O)
-    if length(args) == 2 && args[2] isa Real && args[2] < 0
-        ex = args[1]
-        if args[2] == -1
-            return toexpr(Term(inv, Any[ex]), st)
-        else
-            args = Any[Term(inv, Any[ex]), -args[2]]
-            op = get(st.rewrites, :nanmath, false) ? op : NaNMath.pow
-            return toexpr(Term(op, args), st)
-        end
+    if args[2] isa Real && args[2] < 0
+        args[1] = Term(inv, Any[args[1]])
+        args[2] = -args[2]
+    end
+    if isequal(args[2], 1)
+        return toexpr(args[1], st)
+    end
+    if get(st.rewrites, :nanmath, false) === true && !(args[2] isa Integer)
+        op = NaNMath.pow
+        return toexpr(Term(op, args), st)
     end
-    get(st.rewrites, :nanmath, false) === true || return nothing
-    return toexpr(Term(NaNMath.pow, args), st)
+    return nothing
 end
 
 function function_to_expr(::typeof(SymbolicUtils.ifelse), O, st)
diff --git a/test/code.jl b/test/code.jl
index 0e25437a1..918ef9dcc 100644
--- a/test/code.jl
+++ b/test/code.jl
@@ -100,19 +100,19 @@ nanmath_st.rewrites[:nanmath] = true
     @test toexpr(NaNMath.pow(a, b), nanmath_st) == :($(NaNMath.pow)(a, b))
 
     @test toexpr(a^2) == :($(^)(a, 2))
-    @test toexpr(a^2, nanmath_st) == :($(NaNMath.pow)(a, 2))
-    @test toexpr(NaNMath.pow(a, 2)) == :($(NaNMath.pow)(a, 2))
-    @test toexpr(NaNMath.pow(a, 2), nanmath_st) == :($(NaNMath.pow)(a, 2))
+    @test toexpr(a^2, nanmath_st) == :($(^)(a, 2))
+    @test toexpr(NaNMath.pow(a, 2)) == :($(^)(a, 2))
+    @test toexpr(NaNMath.pow(a, 2), nanmath_st) == :($(^)(a, 2))
 
     @test toexpr(a^-1) == :($(/)(1, a))
     @test toexpr(a^-1, nanmath_st) == :($(/)(1, a))
-    @test toexpr(NaNMath.pow(a, -1)) == :($(NaNMath.pow)(a, -1))
-    @test toexpr(NaNMath.pow(a, -1), nanmath_st) == :($(NaNMath.pow)(a, -1))
+    @test toexpr(NaNMath.pow(a, -1)) == :($(inv)(a))
+    @test toexpr(NaNMath.pow(a, -1), nanmath_st) == :($(inv)(a))
 
     @test toexpr(a^-2) == :($(/)(1, $(^)(a, 2)))
-    @test toexpr(a^-2, nanmath_st) == :($(/)(1, $(NaNMath.pow)(a, 2)))
-    @test toexpr(NaNMath.pow(a, -2)) == :($(NaNMath.pow)(a, -2))
-    @test toexpr(NaNMath.pow(a, -2), nanmath_st) == :($(NaNMath.pow)(a, -2))
+    @test toexpr(a^-2, nanmath_st) == :($(/)(1, $(^)(a, 2)))
+    @test toexpr(NaNMath.pow(a, -2)) == :($(^)($(inv)(a), 2))
+    @test toexpr(NaNMath.pow(a, -2), nanmath_st) == :($(^)($(inv)(a), 2))
 
     f = GlobalRef(NaNMath, :sin)
     test_repr(toexpr(LiteralExpr(:(let x=1, y=2