1211122111 has 8 divisors (see below), whose sum is σ = 1282689920. Its totient is φ = 1140336792.

The previous prime is 1211122103. The next prime is 1211122127. The reversal of 1211122111 is 1112211121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1211122111 - 2³ = 1211122103 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211122091 and 1211122100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211122141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 192435 + ... + 198628.

It is an arithmetic number, because the mean of its divisors is an integer number (160336240).

Almost surely, 2^1211122111 is an apocalyptic number.

1211122111 is a deficient number, since it is larger than the sum of its proper divisors (71567809).

1211122111 is a wasteful number, since it uses less digits than its factorization.

1211122111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391245.

The product of its digits is 8, while the sum is 13.

The square root of 1211122111 is about 34801.1797357503. The cubic root of 1211122111 is about 1065.9315355429.

Adding to 1211122111 its reverse (1112211121), we get a palindrome (2323333232).

The spelling of 1211122111 in words is "one billion, two hundred eleven million, one hundred twenty-two thousand, one hundred eleven".