OPA129: Eliminate noise on floating op amp input

Part Number:OPA129

Hi,

I am using OPA129 as an non inverting amplifier for an in put range -0.5V to +0.5V , but whenever I dont give an input to the non inverting pin( leaving it floating), It picks up a very small noise( its freq is ~50 Hz ..guessing the AC hum) and amplifies it . I would like to eliminate this noise. Can you please help?

Thank you,

Aditya Teja Damera