311147231 has 2 divisors, whose sum is σ = 311147232. Its totient is φ = 311147230.

The previous prime is 311147227. The next prime is 311147233. The reversal of 311147231 is 132741113.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 311147231 - 2² = 311147227 is a prime.

It is a super-2 number, since 2×311147231² = 193625198717934722, which contains 22 as substring.

Together with 311147233, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 311147197 and 311147206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311147233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155573615 + 155573616.

It is an arithmetic number, because the mean of its divisors is an integer number (155573616).

Almost surely, 2^311147231 is an apocalyptic number.

311147231 is a deficient number, since it is larger than the sum of its proper divisors (1).

311147231 is an equidigital number, since it uses as much as digits as its factorization.

311147231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 504, while the sum is 23.

The square root of 311147231 is about 17639.3659466547. The cubic root of 311147231 is about 677.6237931405.

Adding to 311147231 its reverse (132741113), we get a palindrome (443888344).

The spelling of 311147231 in words is "three hundred eleven million, one hundred forty-seven thousand, two hundred thirty-one".