31222021111 has 4 divisors (see below), whose sum is σ = 32865285400. Its totient is φ = 29578756824.

The previous prime is 31222021099. The next prime is 31222021153. The reversal of 31222021111 is 11112022213.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31222021111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31222021711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 821632116 + ... + 821632153.

It is an arithmetic number, because the mean of its divisors is an integer number (8216321350).

Almost surely, 2^31222021111 is an apocalyptic number.

31222021111 is a deficient number, since it is larger than the sum of its proper divisors (1643264289).

31222021111 is a wasteful number, since it uses less digits than its factorization.

31222021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643264288.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 31222021111 its reverse (11112022213), we get a palindrome (42334043324).

The spelling of 31222021111 in words is "thirty-one billion, two hundred twenty-two million, twenty-one thousand, one hundred eleven".