21111122231 has 8 divisors (see below), whose sum is σ = 21461052000. Its totient is φ = 20761316640.

The previous prime is 21111122183. The next prime is 21111122237. The reversal of 21111122231 is 13222111112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21111122231 - 2¹⁸ = 21110860087 is a prime.

It is a super-2 number, since 2×21111122231² (a number of 21 digits) 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 (21111122237) 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 in 7 ways as a sum of consecutive naturals, for example, 350225 + ... + 406053.

It is an arithmetic number, because the mean of its divisors is an integer number (2682631500).

Almost surely, 2^21111122231 is an apocalyptic number.

21111122231 is a deficient number, since it is larger than the sum of its proper divisors (349929769).

21111122231 is an equidigital number, since it uses as much as digits as its factorization.

21111122231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62089.

The product of its digits is 48, while the sum is 17.

Adding to 21111122231 its reverse (13222111112), we get a palindrome (34333233343).

The spelling of 21111122231 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-two thousand, two hundred thirty-one".