1211111222311 has 4 divisors (see below), whose sum is σ = 1211526415912. Its totient is φ = 1210696028712.

The previous prime is 1211111222303. The next prime is 1211111222333. The reversal of 1211111222311 is 1132221111121.

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 1211111222311 - 2³ = 1211111222303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211111229311) 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, 207592425 + ... + 207598258.

It is an arithmetic number, because the mean of its divisors is an integer number (302881603978).

Almost surely, 2^{1211111222311} is an apocalyptic number.

1211111222311 is a deficient number, since it is larger than the sum of its proper divisors (415193601).

1211111222311 is an equidigital number, since it uses as much as digits as its factorization.

1211111222311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415193600.

The product of its digits is 48, while the sum is 19.

Adding to 1211111222311 its reverse (1132221111121), we get a palindrome (2343332333432).

The spelling of 1211111222311 in words is "one trillion, two hundred eleven billion, one hundred eleven million, two hundred twenty-two thousand, three hundred eleven".