21112321211 has 2 divisors, whose sum is σ = 21112321212. Its totient is φ = 21112321210.

The previous prime is 21112321201. The next prime is 21112321259. The reversal of 21112321211 is 11212321112.

It is a happy number.

It is a m-pointer prime, because the next prime (21112321259) can be obtained adding 21112321211 to its product of digits (48).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21112321211 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21112321211.

It is not a weakly prime, because it can be changed into another prime (21112321201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556160605 + 10556160606.

It is an arithmetic number, because the mean of its divisors is an integer number (10556160606).

Almost surely, 2^21112321211 is an apocalyptic number.

21112321211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112321211 is an equidigital number, since it uses as much as digits as its factorization.

21112321211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 17.

Adding to 21112321211 its reverse (11212321112), we get a palindrome (32324642323).

Subtracting from 21112321211 its reverse (11212321112), we obtain a palindrome (9900000099).

The spelling of 21112321211 in words is "twenty-one billion, one hundred twelve million, three hundred twenty-one thousand, two hundred eleven".