1311512231 has 2 divisors, whose sum is σ = 1311512232. Its totient is φ = 1311512230.

The previous prime is 1311512227. The next prime is 1311512263. The reversal of 1311512231 is 1322151131.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1311512231 - 2² = 1311512227 is a prime.

It is a super-2 number, since 2×1311512231² = 3440128664125194722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311512131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655756115 + 655756116.

It is an arithmetic number, because the mean of its divisors is an integer number (655756116).

Almost surely, 2^1311512231 is an apocalyptic number.

1311512231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311512231 is an equidigital number, since it uses as much as digits as its factorization.

1311512231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 180, while the sum is 20.

The square root of 1311512231 is about 36214.8067922500. The cubic root of 1311512231 is about 1094.6050523426.

Adding to 1311512231 its reverse (1322151131), we get a palindrome (2633663362).

The spelling of 1311512231 in words is "one billion, three hundred eleven million, five hundred twelve thousand, two hundred thirty-one".