311622431 has 2 divisors, whose sum is σ = 311622432. Its totient is φ = 311622430.

The previous prime is 311622403. The next prime is 311622433. The reversal of 311622431 is 134226113.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311622431 is a prime.

It is a super-2 number, since 2×311622431² = 194217079004699522, which contains 22 as substring.

Together with 311622433, 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 = 311622397 and 311622406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311622433) 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, 155811215 + 155811216.

It is an arithmetic number, because the mean of its divisors is an integer number (155811216).

Almost surely, 2^311622431 is an apocalyptic number.

311622431 is a deficient number, since it is larger than the sum of its proper divisors (1).

311622431 is an equidigital number, since it uses as much as digits as its factorization.

311622431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

The square root of 311622431 is about 17652.8306795256. The cubic root of 311622431 is about 677.9685849356.

Adding to 311622431 its reverse (134226113), we get a palindrome (445848544).

The spelling of 311622431 in words is "three hundred eleven million, six hundred twenty-two thousand, four hundred thirty-one".