21011221022089 has 2 divisors, whose sum is σ = 21011221022090. Its totient is φ = 21011221022088.

The previous prime is 21011221022087. The next prime is 21011221022093. The reversal of 21011221022089 is 98022012211012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20050021175625 + 961199846464 = 4477725^2 + 980408^2 .

It is a cyclic number.

It is not a de Polignac number, because 21011221022089 - 2¹ = 21011221022087 is a prime.

Together with 21011221022087, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21011221022089.

It is not a weakly prime, because it can be changed into another prime (21011221022087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505610511044 + 10505610511045.

It is an arithmetic number, because the mean of its divisors is an integer number (10505610511045).

Almost surely, 2^{21011221022089} is an apocalyptic number.

It is an amenable number.

21011221022089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011221022089 is an equidigital number, since it uses as much as digits as its factorization.

21011221022089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

The spelling of 21011221022089 in words is "twenty-one trillion, eleven billion, two hundred twenty-one million, twenty-two thousand, eighty-nine".