311631223 has 2 divisors, whose sum is σ = 311631224. Its totient is φ = 311631222.

The previous prime is 311631193. The next prime is 311631239. The reversal of 311631223 is 322136113.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 311631223 - 2¹³ = 311623031 is a prime.

It is a super-2 number, since 2×311631223² = 194228038296951458, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 311631194 and 311631203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311631253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155815611 + 155815612.

It is an arithmetic number, because the mean of its divisors is an integer number (155815612).

Almost surely, 2^311631223 is an apocalyptic number.

311631223 is a deficient number, since it is larger than the sum of its proper divisors (1).

311631223 is an equidigital number, since it uses as much as digits as its factorization.

311631223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 22.

The square root of 311631223 is about 17653.0797029867. The cubic root of 311631223 is about 677.9749608606.

Adding to 311631223 its reverse (322136113), we get a palindrome (633767336).

The spelling of 311631223 in words is "three hundred eleven million, six hundred thirty-one thousand, two hundred twenty-three".