21230111121 has 4 divisors (see below), whose sum is σ = 28306814832. Its totient is φ = 14153407412.

The previous prime is 21230111101. The next prime is 21230111129. The reversal of 21230111121 is 12111103212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21230111121 - 2²³ = 21221722513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21230111121.

It is not an unprimeable number, because it can be changed into a prime (21230111129) 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 3 ways as a sum of consecutive naturals, for example, 3538351851 + ... + 3538351856.

It is an arithmetic number, because the mean of its divisors is an integer number (7076703708).

Almost surely, 2^21230111121 is an apocalyptic number.

It is an amenable number.

21230111121 is a deficient number, since it is larger than the sum of its proper divisors (7076703711).

21230111121 is an equidigital number, since it uses as much as digits as its factorization.

21230111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7076703710.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21230111121 its reverse (12111103212), we get a palindrome (33341214333).

The spelling of 21230111121 in words is "twenty-one billion, two hundred thirty million, one hundred eleven thousand, one hundred twenty-one".