31223011111 has 2 divisors, whose sum is σ = 31223011112. Its totient is φ = 31223011110.

The previous prime is 31223011103. The next prime is 31223011133. The reversal of 31223011111 is 11111032213.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31223011111 - 2³ = 31223011103 is a prime.

It is a super-3 number, since 3×31223011111³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31223011181) 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, 15611505555 + 15611505556.

It is an arithmetic number, because the mean of its divisors is an integer number (15611505556).

Almost surely, 2^31223011111 is an apocalyptic number.

31223011111 is a deficient number, since it is larger than the sum of its proper divisors (1).

31223011111 is an equidigital number, since it uses as much as digits as its factorization.

31223011111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 31223011111 its reverse (11111032213), we get a palindrome (42334043324).

The spelling of 31223011111 in words is "thirty-one billion, two hundred twenty-three million, eleven thousand, one hundred eleven".