The square root of 4456321. (The reversal of 4456321 is 1112 squared.)
The smallest "prime year" of the 22nd century. The next prime years are 2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161, and 2179.
2111 in base b is prime for all values of b between 2 and 11, with the exception of b=6. [Necula]
The first salmonella outbreak associated with peanut butter
had product code 2111 on the lid.
2111 = 1 + 2^2 + 2^3 + 2^5 + 2^7 + 2^11. The exponents are consecutive primes. [Noe]
The smallest prime that together with its "look-and-say"
description from the left in the digit-frequency order
(i.e., 2 once, 1 thrice) forms a twin prime pair (2111,
The smaller of only two primes less than a googol formed by concatenating in descending order the first n multi-digit numbers ending with 1, (case n=2). The other is 41312111 for n=4. [Loungrides]
(There is one curio for this number that has not yet been approved by an editor.)