How do you prevalent are bacteria?

Bacteria are incredibly prevalent and can be found in nearly every environment on Earth, including soil, water, air, and even extreme habitats like hot springs and deep-sea vents. They constitute a significant portion of the biomass on the planet, with estimates suggesting that there are about 5 nonillion (5 x 10^30) bacterial cells in total. In the human body alone, bacteria outnumber human cells by roughly ten to one, playing crucial roles in processes like digestion and immunity. Their ubiquity and adaptability make them essential to ecosystems and various biogeochemical cycles.