21013232111 has 2 divisors, whose sum is σ = 21013232112. Its totient is φ = 21013232110.

The previous prime is 21013232089. The next prime is 21013232159. The reversal of 21013232111 is 11123231012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21013232111 - 2¹⁰ = 21013231087 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21013232111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21013232171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506616055 + 10506616056.

It is an arithmetic number, because the mean of its divisors is an integer number (10506616056).

Almost surely, 2^21013232111 is an apocalyptic number.

21013232111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21013232111 is an equidigital number, since it uses as much as digits as its factorization.

21013232111 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 21013232111 its reverse (11123231012), we get a palindrome (32136463123).

The spelling of 21013232111 in words is "twenty-one billion, thirteen million, two hundred thirty-two thousand, one hundred eleven".