21113121233 has 4 divisors (see below), whose sum is σ = 22224338160. Its totient is φ = 20001904308.

The previous prime is 21113121229. The next prime is 21113121317. The reversal of 21113121233 is 33212131112.

It is a happy number.

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 21113121233 - 2² = 21113121229 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21113124233) 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, 555608435 + ... + 555608472.

It is an arithmetic number, because the mean of its divisors is an integer number (5556084540).

Almost surely, 2^21113121233 is an apocalyptic number.

It is an amenable number.

21113121233 is a deficient number, since it is larger than the sum of its proper divisors (1111216927).

21113121233 is a wasteful number, since it uses less digits than its factorization.

21113121233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1111216926.

The product of its digits is 216, while the sum is 20.

Adding to 21113121233 its reverse (33212131112), we get a palindrome (54325252345).

The spelling of 21113121233 in words is "twenty-one billion, one hundred thirteen million, one hundred twenty-one thousand, two hundred thirty-three".