Methods, apparatus, systems, and articles of manufacture for detecting anomalous activity of an IoT device are disclosed. An example apparatus includes a communications aggregator to aggregate communications from a device communicating via a communications interface, a statistical property extractor to extract statistical properties of the aggregated communications, an image generator to generate an image based on the extracted statistical properties, a persona identifier to identify a persona associated with the device, and a machine learning model trainer to train a machine learning model using the generated image and the persona.