This was given by my mom. She took one of the offset from her friend and gave it to me. I believe that this is Echinopsis calochlora. Also a very tough cactus, it do grow under neglect and without sunlight.
However, this is result of not taking good care of it. It suffer from serious etiolation (not enough light). The top of this cactus was chipped away when a strong wind cause it to toppled over. Looking at how it continue to strive, it feel so proud of it.
It is also very prolific in producing offsets. More offsets are growing out soon in this cactus. The top few also suffer from etiolation, but once I move them to a brighter location, those at the bottom which grow out later were more globular.