21323011121 has 2 divisors, whose sum is σ = 21323011122. Its totient is φ = 21323011120.

The previous prime is 21323011109. The next prime is 21323011147. The reversal of 21323011121 is 12111032312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19583203600 + 1739807521 = 139940^2 + 41711^2 .

It is a cyclic number.

It is not a de Polignac number, because 21323011121 - 2⁶ = 21323011057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21323011121.

It is not a weakly prime, because it can be changed into another prime (21323011621) 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, 10661505560 + 10661505561.

It is an arithmetic number, because the mean of its divisors is an integer number (10661505561).

Almost surely, 2^21323011121 is an apocalyptic number.

It is an amenable number.

21323011121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323011121 is an equidigital number, since it uses as much as digits as its factorization.

21323011121 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21323011121 its reverse (12111032312), we get a palindrome (33434043433).

The spelling of 21323011121 in words is "twenty-one billion, three hundred twenty-three million, eleven thousand, one hundred twenty-one".