Mqtt switch "on" with random value as message?

I have a mqtt message coming in like

/swtich/1 123

Where the 123 is a reading which isn’t important but changes every time. Basically, if I see ANY value from this topic I want to toggle the switch on but I don’t see how this possible since it seems I either have to provide a value or it will default to true.

 - platform: mqtt¬
      name: "Switch"¬
      state_topic: "power/"¬
      qos: 1¬
      retain: true¬
      payload_on: "on"¬
      payload_off: "off"¬