1211323211 has 4 divisors (see below), whose sum is σ = 1384369392. Its totient is φ = 1038277032.

The previous prime is 1211323193. The next prime is 1211323231. The reversal of 1211323211 is 1123231121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1123231121 = 41 ⋅27395881.

It is a cyclic number.

It is not a de Polignac number, because 1211323211 - 2²² = 1207128907 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211323211.

It is not an unprimeable number, because it can be changed into a prime (1211323231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86523080 + ... + 86523093.

It is an arithmetic number, because the mean of its divisors is an integer number (346092348).

Almost surely, 2^1211323211 is an apocalyptic number.

1211323211 is a deficient number, since it is larger than the sum of its proper divisors (173046181).

1211323211 is an equidigital number, since it uses as much as digits as its factorization.

1211323211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173046180.

The product of its digits is 72, while the sum is 17.

The square root of 1211323211 is about 34804.0688856921. The cubic root of 1211323211 is about 1065.9905295856.

Adding to 1211323211 its reverse (1123231121), we get a palindrome (2334554332).

The spelling of 1211323211 in words is "one billion, two hundred eleven million, three hundred twenty-three thousand, two hundred eleven".