111111212209 has 2 divisors, whose sum is σ = 111111212210. Its totient is φ = 111111212208.

The previous prime is 111111212207. The next prime is 111111212227. The reversal of 111111212209 is 902212111111.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 96940690609 + 14170521600 = 311353^2 + 119040^2 .

It is a cyclic number.

It is not a de Polignac number, because 111111212209 - 2¹ = 111111212207 is a prime.

Together with 111111212207, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 111111212209.

It is not a weakly prime, because it can be changed into another prime (111111212207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55555606104 + 55555606105.

It is an arithmetic number, because the mean of its divisors is an integer number (55555606105).

Almost surely, 2^111111212209 is an apocalyptic number.

It is an amenable number.

111111212209 is a deficient number, since it is larger than the sum of its proper divisors (1).

111111212209 is an equidigital number, since it uses as much as digits as its factorization.

111111212209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 22.

The spelling of 111111212209 in words is "one hundred eleven billion, one hundred eleven million, two hundred twelve thousand, two hundred nine".