It's a credit to how good Isaac Newton was at physics and math that people rarely mention that time he threatened to burn his mother's house down, or the equally-baffling time he stuck a number of needles into his own eyeballs to see what would happen.
Yes, when Newton wasn't revolutionizing our notions of motion and gravity he was, by today's standards, a bit of a weird dude. As well as dedicating a lot of his spare time to the study of alchemy – a medieval belief that metals could be turned into gold – Newton had a keen interest in the occult and the Biblical apocalypse.
In fact, in a few private pieces of speculation likely not meant to be seen publicly, Newton went about attempting to predict the end of the world, based on his Protestant understanding of the Bible and the events that followed. In one attempt, written on a letter slip next to real math calculations of the non-apocalypse type, Newton apparently made reference to the year 2060:
Prop. 1. The 2300 prophetick days did not commence before the rise of the little horn of the He Goat.
2 Those day [sic] did not commence a[f]ter the destruction of Jerusalem & ye Temple by the Romans A.[D.] 70.
3 The time times & half a time did not commence before the year 800 in wch the Popes supremacy commenced
4 They did not commence after the re[ig]ne of Gregory the 7th. 1084
5 The 1290 days did not commence b[e]fore the year 842.
6 They did not commence after the reigne of Pope Greg. 7th. 1084
7 The diffence [sic] between the 1290 & 1335 days are a parts of the seven weeks.
Therefore the 2300 years do not end before ye year 2132 nor after 2370. The time times & half time do n[o]t end before 2060 nor after  The 1290 days do not [end] before 2090 nor after .
Newton believed in apocalyptic visions in the Bible, where a battle of Armageddon would occur between “Gog and Magog” at the end of days. Newton probably only has himself to blame for talking of the "rise of the little horn of the He Goat" and leaving his notes lying around, but it should be noted that he was not predicting the end of the world would occur in 2060, so much as the end of an era.
"Newton was convinced that Christ would return around this date and establish a global Kingdom of peace," Stephen D. Snobelen, now professor of the history of science and technology at the University of King's College in Halifax wrote in 2003. "'Babylon' (the corrupt Trinitarian Church) would also fall and the true Gospel would be preached openly."
Newton, though he made such a prediction to himself, did not like the practice of predicting the end of the world because of the damage it did to religious prophesies that occurred when the apocalypse didn't.
"So then the time times & half a time are 42 months or 1260 days or three years & an half, recconing twelve months to a yeare & 30 days to a month as was done in the Calendar of the primitive year. And the days of short lived Beasts being put for the years of lived kingdoms, the period of 1260 days, if dated from the complete conquest of the three kings A.C. 800, will end A.C. 2060. It may end later, but I see no reason for its ending sooner."
He wrote in one prediction, which again he likely did not want to be seen:
"This I mention not to assert when the time of the end shall be, but to put a stop to the rash conjectures of fancifull men who are frequently predicting the time of the end, & by doing so bring the sacred prophesies into discredit as often as their predictions fail. Christ comes as a thief in the night, & it is not for us to know the times & seasons wch God hath put into his own breast."
Unfortunately for Newton, enough time has passed that his predictions will soon fail, placing him into the same category of the "fancifull men" discrediting prophecies as a whole.