111212221111 has 2 divisors, whose sum is σ = 111212221112. Its totient is φ = 111212221110.

The previous prime is 111212221079. The next prime is 111212221121. The reversal of 111212221111 is 111122212111.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 111212221111 - 2⁵ = 111212221079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111212221121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55606110555 + 55606110556.

It is an arithmetic number, because the mean of its divisors is an integer number (55606110556).

Almost surely, 2^111212221111 is an apocalyptic number.

111212221111 is a deficient number, since it is larger than the sum of its proper divisors (1).

111212221111 is an equidigital number, since it uses as much as digits as its factorization.

111212221111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16, while the sum is 16.

Adding to 111212221111 its reverse (111122212111), we get a palindrome (222334433222).

The spelling of 111212221111 in words is "one hundred eleven billion, two hundred twelve million, two hundred twenty-one thousand, one hundred eleven".