In the 1870's, a sailor was swallowed by a sperm whale after falling out of his (small) whaling boat.
His colleagues were able to kill the whale within 5 minutes.
They cut the whale open and retrieved their colleague.
He WAS still alive.
They took him back to the ship,where sadly he died in about 30minutes.
You might ask why he died if he was retrieved alive from the whale?
Sadly,he had been in the whale's stomach for just too long,and the stomach acid had stripped most of the layers of his skin;he died from the shock.
So,if a blue whale swallowed you,you would be digested in no time at all!