1211242111 has 2 divisors, whose sum is σ = 1211242112. Its totient is φ = 1211242110.

The previous prime is 1211242091. The next prime is 1211242127. The reversal of 1211242111 is 1112421121.

It is an a-pointer prime, because the next prime (1211242127) can be obtained adding 1211242111 to its sum of digits (16).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1211242111 - 2²⁷ = 1077024383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211242411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605621055 + 605621056.

It is an arithmetic number, because the mean of its divisors is an integer number (605621056).

Almost surely, 2^1211242111 is an apocalyptic number.

1211242111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211242111 is an equidigital number, since it uses as much as digits as its factorization.

1211242111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32, while the sum is 16.

The square root of 1211242111 is about 34802.9037725302. The cubic root of 1211242111 is about 1065.9667391387.

Adding to 1211242111 its reverse (1112421121), we get a palindrome (2323663232).

It can be divided in two parts, 1 and 211242111, that added together give a palindrome (211242112).

The spelling of 1211242111 in words is "one billion, two hundred eleven million, two hundred forty-two thousand, one hundred eleven".