God says that He assigned 19 angels to guard Hell, and He made their count "19" so that believers shall increase their faith.
[Quran 74.30-31] Over it are Nineteen. We have appointed only angels to be wardens of the Fire, and made their count to be a stumbling block for those who disbelieve; so that those given the Scripture may attain certainty; and those who believe may increase their faith; and those given the Scripture and the believers may not doubt. And those in whose hearts is sickness and the unbelievers may say, "What did Allah intend by this parable?" Thus Allah leads astray whom He wills, and guides whom He wills. None knows the soldiers of your Lord except Him. This is nothing but a reminder for humans.
(In the Christian Bible Jesus insists that the only sign we should verify is him being in the grave for three days and three nights (Matthew 12:38-40). So we are checking: He was crucified on Friday afternoon, the day before the Sabbath (Mark 15:42), and then he was resurrected on Sunday morning (Mark 16:9). Between Friday afternoon and Sunday morning there is 36 hours. Can anyone fit within those 36 hours three days and three nights?)