21230111233 has 4 divisors (see below), whose sum is σ = 21238963200. Its totient is φ = 21221259268.

The previous prime is 21230111209. The next prime is 21230111237. The reversal of 21230111233 is 33211103212.

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 a de Polignac number, because none of the positive numbers 2^k-21230111233 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21230111233.

It is not an unprimeable number, because it can be changed into a prime (21230111237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4422385 + ... + 4427182.

It is an arithmetic number, because the mean of its divisors is an integer number (5309740800).

Almost surely, 2^21230111233 is an apocalyptic number.

It is an amenable number.

21230111233 is a deficient number, since it is larger than the sum of its proper divisors (8851967).

21230111233 is an equidigital number, since it uses as much as digits as its factorization.

21230111233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8851966.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21230111233 its reverse (33211103212), we get a palindrome (54441214445).

The spelling of 21230111233 in words is "twenty-one billion, two hundred thirty million, one hundred eleven thousand, two hundred thirty-three".