diff --git a/mysql-test/r/partition.result b/mysql-test/r/partition.result
index 6f72068c0b7..5848618ff65 100644
--- a/mysql-test/r/partition.result
+++ b/mysql-test/r/partition.result
@@ -1,5 +1,21 @@
 drop table if exists t1;
 create table t1 (a int)
+partition by key(a)
+partitions 0.2+e1;
+ERROR 42000: Only normal integers allowed as number here near '0.2+e1' at line 3
+create table t1 (a int)
+partition by key(a)
+partitions -1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-1' at line 3
+create table t1 (a int)
+partition by key(a)
+partitions 1.5;
+ERROR 42000: Only normal integers allowed as number here near '1.5' at line 3
+create table t1 (a int)
+partition by key(a)
+partitions 1e+300;
+ERROR 42000: Only normal integers allowed as number here near '1e+300' at line 3
+create table t1 (a int)
 partition by list (a)
 (partition p0 values in (1));
 create procedure pz()
diff --git a/mysql-test/t/partition.test b/mysql-test/t/partition.test
index 6e6e4cb304d..854db01155b 100644
--- a/mysql-test/t/partition.test
+++ b/mysql-test/t/partition.test
@@ -9,6 +9,25 @@
 drop table if exists t1;
 --enable_warnings
 
+#
+# Bug 15890: Strange number of partitions accepted
+#
+-- error 1064
+create table t1 (a int)
+partition by key(a)
+partitions 0.2+e1;
+-- error 1064
+create table t1 (a int)
+partition by key(a)
+partitions -1;
+-- error 1064
+create table t1 (a int)
+partition by key(a)
+partitions 1.5;
+-- error 1064
+create table t1 (a int)
+partition by key(a)
+partitions 1e+300;
 #
 # Bug 19309 Partitions: Crash if double procedural alter
 #
diff --git a/sql/share/errmsg.txt b/sql/share/errmsg.txt
index 297e4c5c374..62a362d0859 100644
--- a/sql/share/errmsg.txt
+++ b/sql/share/errmsg.txt
@@ -5954,3 +5954,5 @@ ER_BAD_LOG_ENGINE
         eng "One can use only CSV and MyISAM engines for the log tables"
 ER_CANT_DROP_LOG_TABLE
         eng "Cannot drop log table if log is enabled"
+ER_ONLY_INTEGERS_ALLOWED
+        eng "Only normal integers allowed as number here"
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index eb3d0d40817..dc6f6277043 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -752,10 +752,10 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
         ev_alter_on_schedule_completion opt_ev_rename_to opt_ev_sql_stmt
 
 %type <ulong_num>
-	ulong_num merge_insert_types
+	ulong_num real_ulong_num merge_insert_types
 
 %type <ulonglong_number>
-	ulonglong_num size_number
+	ulonglong_num real_ulonglong_num size_number
 
 %type <p_elem_value>
         part_bit_expr
@@ -3097,7 +3097,7 @@ opt_ts_redo_buffer_size:
           };
 
 opt_ts_nodegroup:
-          NODEGROUP_SYM opt_equal ulong_num
+          NODEGROUP_SYM opt_equal real_ulong_num
           {
             LEX *lex= Lex;
             if (lex->alter_tablespace_info->nodegroup_id != UNDEF_NODEGROUP)
@@ -3156,7 +3156,7 @@ ts_wait:
           };
 
 size_number:
-          ulong_num { $$= $1;}
+          real_ulong_num { $$= $1;}
           | IDENT
           {
             ulonglong number, test_number;
@@ -3395,7 +3395,7 @@ sub_part_func:
 
 opt_no_parts:
         /* empty */ {}
-        | PARTITIONS_SYM ulong_num 
+        | PARTITIONS_SYM real_ulong_num 
         { 
           uint no_parts= $2;
           LEX *lex= Lex;
@@ -3459,7 +3459,7 @@ part_func_expr:
 
 opt_no_subparts:
         /* empty */ {}
-        | SUBPARTITIONS_SYM ulong_num
+        | SUBPARTITIONS_SYM real_ulong_num
         {
           uint no_parts= $2;
           LEX *lex= Lex;
@@ -3799,11 +3799,11 @@ opt_part_option:
           lex->part_info->curr_part_elem->engine_type= $4;
           lex->part_info->default_engine_type= $4;
         }
-        | NODEGROUP_SYM opt_equal ulong_num
+        | NODEGROUP_SYM opt_equal real_ulong_num
         { Lex->part_info->curr_part_elem->nodegroup_id= $3; }
-        | MAX_ROWS opt_equal ulonglong_num
+        | MAX_ROWS opt_equal real_ulonglong_num
         { Lex->part_info->curr_part_elem->part_max_rows= $3; }
-        | MIN_ROWS opt_equal ulonglong_num
+        | MIN_ROWS opt_equal real_ulonglong_num
         { Lex->part_info->curr_part_elem->part_min_rows= $3; }
         | DATA_SYM DIRECTORY_SYM opt_equal TEXT_STRING_sys
         { Lex->part_info->curr_part_elem->data_file_name= $4.str; }
@@ -4933,7 +4933,7 @@ alter_commands:
             lex->check_opt.init();
           }
           opt_mi_repair_type
-        | COALESCE PARTITION_SYM opt_no_write_to_binlog ulong_num
+        | COALESCE PARTITION_SYM opt_no_write_to_binlog real_ulong_num
           {
             LEX *lex= Lex;
 	    lex->alter_info.flags|= ALTER_COALESCE_PARTITION;
@@ -4981,7 +4981,7 @@ add_part_extra:
           LEX *lex= Lex;
           lex->part_info->no_parts= lex->part_info->partitions.elements;
         }
-        | PARTITIONS_SYM ulong_num
+        | PARTITIONS_SYM real_ulong_num
         {
           LEX *lex= Lex;
           lex->part_info->no_parts= $2;
@@ -7516,7 +7516,15 @@ ulong_num:
 	| ULONGLONG_NUM { int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
         | DECIMAL_NUM   { int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
 	| FLOAT_NUM	{ int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
-	;
+        ;
+
+real_ulong_num:
+          NUM           { int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
+	| HEX_NUM       { $$= (ulong) strtol($1.str, (char**) 0, 16); }
+	| LONG_NUM      { int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
+	| ULONGLONG_NUM { int error; $$= (ulong) my_strtoll10($1.str, (char**) 0, &error); }
+        | dec_num_error { YYABORT; }
+        ;
 
 ulonglong_num:
 	NUM	    { int error; $$= (ulonglong) my_strtoll10($1.str, (char**) 0, &error); }
@@ -7526,6 +7534,23 @@ ulonglong_num:
 	| FLOAT_NUM { int error; $$= (ulonglong) my_strtoll10($1.str, (char**) 0, &error); }
 	;
 
+real_ulonglong_num:
+	NUM	    { int error; $$= (ulonglong) my_strtoll10($1.str, (char**) 0, &error); }
+	| ULONGLONG_NUM { int error; $$= (ulonglong) my_strtoll10($1.str, (char**) 0, &error); }
+	| LONG_NUM  { int error; $$= (ulonglong) my_strtoll10($1.str, (char**) 0, &error); }
+        | dec_num_error { YYABORT; }
+        ;
+
+dec_num_error:
+        dec_num
+        { yyerror(ER(ER_ONLY_INTEGERS_ALLOWED)); }
+        ;
+
+dec_num:
+        DECIMAL_NUM
+	| FLOAT_NUM
+        ;
+
 procedure_clause:
 	/* empty */
 	| PROCEDURE ident			/* Procedure name */