311223431 has 4 divisors (see below), whose sum is σ = 311586600. Its totient is φ = 310860264.

The previous prime is 311223427. The next prime is 311223443. The reversal of 311223431 is 134322113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 134322113 = 29 ⋅4631797.

It is a cyclic number.

It is not a de Polignac number, because 311223431 - 2² = 311223427 is a prime.

It is a super-2 number, since 2×311223431² = 193720048006823522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311223421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180296 + ... + 182013.

It is an arithmetic number, because the mean of its divisors is an integer number (77896650).

Almost surely, 2^311223431 is an apocalyptic number.

311223431 is a deficient number, since it is larger than the sum of its proper divisors (363169).

311223431 is an equidigital number, since it uses as much as digits as its factorization.

311223431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363168.

The product of its digits is 432, while the sum is 20.

The square root of 311223431 is about 17641.5257560110. The cubic root of 311223431 is about 677.6791053457.

Adding to 311223431 its reverse (134322113), we get a palindrome (445545544).

The spelling of 311223431 in words is "three hundred eleven million, two hundred twenty-three thousand, four hundred thirty-one".