1311211031 has 16 divisors (see below), whose sum is σ = 1445209920. Its totient is φ = 1182263040.

The previous prime is 1311211019. The next prime is 1311211049. The reversal of 1311211031 is 1301121131.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1311211031 - 2²² = 1307016727 is a prime.

It is a super-2 number, since 2×1311211031² = 3438548735632165922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1311210997 and 1311211015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311211051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94091 + ... + 107123.

It is an arithmetic number, because the mean of its divisors is an integer number (90325620).

Almost surely, 2^1311211031 is an apocalyptic number.

1311211031 is a deficient number, since it is larger than the sum of its proper divisors (133998889).

1311211031 is a wasteful number, since it uses less digits than its factorization.

1311211031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13226.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1311211031 is about 36210.6480334169. The cubic root of 1311211031 is about 1094.5212507899.

Adding to 1311211031 its reverse (1301121131), we get a palindrome (2612332162).

The spelling of 1311211031 in words is "one billion, three hundred eleven million, two hundred eleven thousand, thirty-one".