ansible - type is not maintained, even with |int

output

TASK [Gathering Facts] *********************************************************************************************************************************************************************************************************************************************************
ok: [localhost]

TASK [debug] *******************************************************************************************************************************************************************************************************************************************************************
ok: [localhost] => {
    "ansible_memtotal_mb": 16384
}

TASK [command] *****************************************************************************************************************************************************************************************************************************************************************
changed: [localhost]

TASK [debug] *******************************************************************************************************************************************************************************************************************************************************************
ok: [localhost] => {
    "mem": {
        "changed": true,
        "cmd": "echo 12345",
        "delta": "0:00:00.007038",
        "end": "2017-10-05 14:37:32.778004",
        "failed": false,
        "rc": 0,
        "start": "2017-10-05 14:37:32.770966",
        "stderr": "",
        "stderr_lines": [],
        "stdout": "12345",
        "stdout_lines": [
            "12345"
        ]
    }
}

TASK [set_fact] ****************************************************************************************************************************************************************************************************************************************************************
ok: [localhost]

TASK [debug] *******************************************************************************************************************************************************************************************************************************************************************
ok: [localhost] => {
    "ansible_memtotal_mb": "12345"
}

play.yml

---
- hosts: localhost
  gather_facts: True
  connection: local
  tasks:
    - debug: 
        var: ansible_memtotal_mb

    - shell: echo 12345
      register: mem

    - debug:
        var: mem
        
    - set_fact:
        ansible_memtotal_mb: "{{ mem.stdout|int }}"

    - debug: 
        var: ansible_memtotal_mb