diff --git a/src/evalvars.c b/src/evalvars.c
index 2bbc355..25d23c8 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -120,8 +120,9 @@
     {VV_NAME("errors",		 VAR_LIST), 0},
     {VV_NAME("false",		 VAR_BOOL), VV_RO},
     {VV_NAME("true",		 VAR_BOOL), VV_RO},
-    {VV_NAME("null",		 VAR_SPECIAL), VV_RO},
     {VV_NAME("none",		 VAR_SPECIAL), VV_RO},
+    {VV_NAME("null",		 VAR_SPECIAL), VV_RO},
+    {VV_NAME("numbersize",	 VAR_NUMBER), VV_RO},
     {VV_NAME("vim_did_enter",	 VAR_NUMBER), VV_RO},
     {VV_NAME("testing",		 VAR_NUMBER), 0},
     {VV_NAME("t_number",	 VAR_NUMBER), VV_RO},
@@ -229,6 +230,7 @@
     set_vim_var_nr(VV_TRUE, VVAL_TRUE);
     set_vim_var_nr(VV_NONE, VVAL_NONE);
     set_vim_var_nr(VV_NULL, VVAL_NULL);
+    set_vim_var_nr(VV_NUMBERSIZE, sizeof(varnumber_T) * 8);
 
     set_vim_var_nr(VV_TYPE_NUMBER,  VAR_TYPE_NUMBER);
     set_vim_var_nr(VV_TYPE_STRING,  VAR_TYPE_STRING);