21321230111 has 2 divisors, whose sum is σ = 21321230112. Its totient is φ = 21321230110.

The previous prime is 21321230101. The next prime is 21321230137. The reversal of 21321230111 is 11103212312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21321230111 - 2¹⁰ = 21321229087 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21321230111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21321230101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660615055 + 10660615056.

It is an arithmetic number, because the mean of its divisors is an integer number (10660615056).

Almost surely, 2^21321230111 is an apocalyptic number.

21321230111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21321230111 is an equidigital number, since it uses as much as digits as its factorization.

21321230111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21321230111 its reverse (11103212312), we get a palindrome (32424442423).

It can be divided in two parts, 213212301 and 11, that added together give a palindrome (213212312).

The spelling of 21321230111 in words is "twenty-one billion, three hundred twenty-one million, two hundred thirty thousand, one hundred eleven".