In the 1980s, Samuel Yates defined a titanic prime to be a prime number of at least 1000 decimal digits. The smallest titanic prime is 10^999 + 7. As of 1990, more than 1400 were known. By 1995, more than 10000 were known, and many tens of thousands are known today. The largest prime number known as of December 2018 is the Mersenne prime 2^82589933 - 1, which has a whopping 24862048 decimal digits. The first few titanic primes are 10^999 + n for n = 7, 663, 2121, 2593, 3561, 4717, 5863, 9459, 11239, ... (OEIS A074282).

gigantic prime | large number | Mersenne prime | prime number | probable prime | Sierpiński number of the second kind