1212220111 has 2 divisors, whose sum is σ = 1212220112. Its totient is φ = 1212220110.

The previous prime is 1212220091. The next prime is 1212220117. The reversal of 1212220111 is 1110222121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1212220111 - 2⁹ = 1212219599 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212220091 and 1212220100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212220117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606110055 + 606110056.

It is an arithmetic number, because the mean of its divisors is an integer number (606110056).

Almost surely, 2^1212220111 is an apocalyptic number.

1212220111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212220111 is an equidigital number, since it uses as much as digits as its factorization.

1212220111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1212220111 is about 34816.9514891812. The cubic root of 1212220111 is about 1066.2535617866.

Adding to 1212220111 its reverse (1110222121), we get a palindrome (2322442232).

The spelling of 1212220111 in words is "one billion, two hundred twelve million, two hundred twenty thousand, one hundred eleven".