It's roughly as many words as are spoken worldwide in 2.5 seconds, assuming 7450 words per person per day. It's very probably less than the number of English words spoken in a minute. It's also about the number of words you can expect to speak in 550 years. That means there might be people alive who've spoken that many words, given the variance of word-production counts.

So, a near inconceivable quantity for one person, but a minute fraction of total human communication.

In the context you started out talking about -- making a backup -- mentally grasping how much data that is as text seems far less relevant than mentally grasping how much data that is as a fraction of the storage capacity of a phone, or grasping it as an amount of time required to transfer it from one network location to another.

It sounds like you've switched contexts along the way, though I'm not really sure to what.