311242231 has 2 divisors, whose sum is σ = 311242232. Its totient is φ = 311242230.

The previous prime is 311242229. The next prime is 311242237. The reversal of 311242231 is 132242113.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 311242231 - 2¹ = 311242229 is a prime.

It is a super-2 number, since 2×311242231² = 193743452715714722, which contains 22 as substring.

Together with 311242229, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 311242199 and 311242208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311242237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155621115 + 155621116.

It is an arithmetic number, because the mean of its divisors is an integer number (155621116).

Almost surely, 2^311242231 is an apocalyptic number.

311242231 is a deficient number, since it is larger than the sum of its proper divisors (1).

311242231 is an equidigital number, since it uses as much as digits as its factorization.

311242231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 19.

The square root of 311242231 is about 17642.0585816962. The cubic root of 311242231 is about 677.6927505380.

Adding to 311242231 its reverse (132242113), we get a palindrome (443484344).

The spelling of 311242231 in words is "three hundred eleven million, two hundred forty-two thousand, two hundred thirty-one".