1311131021111 has 4 divisors (see below), whose sum is σ = 1388256375312. Its totient is φ = 1234005666912.

The previous prime is 1311131021107. The next prime is 1311131021141. The reversal of 1311131021111 is 1111201311131.

It is a happy number.

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 1311131021111 - 2² = 1311131021107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 77125354183 = 1311131021111 / (1 + 3 + 1 + 1 + 1 + 3 + 1 + 0 + 2 + 1 + 1 + 1 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311131021111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311131021141) 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, 38562677075 + ... + 38562677108.

It is an arithmetic number, because the mean of its divisors is an integer number (347064093828).

Almost surely, 2^{1311131021111} is an apocalyptic number.

1311131021111 is a deficient number, since it is larger than the sum of its proper divisors (77125354201).

1311131021111 is an equidigital number, since it uses as much as digits as its factorization.

1311131021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77125354200.

The product of its (nonzero) digits is 18, while the sum is 17.

Adding to 1311131021111 its reverse (1111201311131), we get a palindrome (2422332332242).

The spelling of 1311131021111 in words is "one trillion, three hundred eleven billion, one hundred thirty-one million, twenty-one thousand, one hundred eleven".