1311121211 has 4 divisors (see below), whose sum is σ = 1325853000. Its totient is φ = 1296389424.

The previous prime is 1311121153. The next prime is 1311121249. The reversal of 1311121211 is 1121211131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1311121211 - 2¹⁴ = 1311104827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311121111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7365761 + ... + 7365938.

It is an arithmetic number, because the mean of its divisors is an integer number (331463250).

Almost surely, 2^1311121211 is an apocalyptic number.

1311121211 is a deficient number, since it is larger than the sum of its proper divisors (14731789).

1311121211 is an equidigital number, since it uses as much as digits as its factorization.

1311121211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14731788.

The product of its digits is 12, while the sum is 14.

The square root of 1311121211 is about 36209.4077692525. The cubic root of 1311121211 is about 1094.4962580818.

Adding to 1311121211 its reverse (1121211131), we get a palindrome (2432332342).

It can be divided in two parts, 131 and 1121211, that multiplied together give a palindrome (146878641).

The spelling of 1311121211 in words is "one billion, three hundred eleven million, one hundred twenty-one thousand, two hundred eleven".