# NamespaceAndSerial

> A unique number combining the FullNamespaceId and Serial into a ulong.

## Definition

* **Type:** Property
* **Namespace:** [Unity.Entities](/engine/7000.0/script-reference/unity/entities.md)
* **Assembly:** UnityEngine.EntitiesModule

```csharp
public ulong NamespaceAndSerial { get; }
```