31113112321 has 2 divisors, whose sum is σ = 31113112322. Its totient is φ = 31113112320.

The previous prime is 31113112319. The next prime is 31113112339. The reversal of 31113112321 is 12321131113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30206440000 + 906672321 = 173800^2 + 30111^2 .

It is a cyclic number.

It is not a de Polignac number, because 31113112321 - 2¹ = 31113112319 is a prime.

Together with 31113112319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31113142321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15556556160 + 15556556161.

It is an arithmetic number, because the mean of its divisors is an integer number (15556556161).

Almost surely, 2^31113112321 is an apocalyptic number.

It is an amenable number.

31113112321 is a deficient number, since it is larger than the sum of its proper divisors (1).

31113112321 is an equidigital number, since it uses as much as digits as its factorization.

31113112321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108, while the sum is 19.

Adding to 31113112321 its reverse (12321131113), we get a palindrome (43434243434).

The spelling of 31113112321 in words is "thirty-one billion, one hundred thirteen million, one hundred twelve thousand, three hundred twenty-one".