21000011089 has 2 divisors, whose sum is σ = 21000011090. Its totient is φ = 21000011088.

The previous prime is 21000011063. The next prime is 21000011147. The reversal of 21000011089 is 98011000012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20111494225 + 888516864 = 141815^2 + 29808^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000011089 is a prime.

It is not a weakly prime, because it can be changed into another prime (21000011029) 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, 10500005544 + 10500005545.

It is an arithmetic number, because the mean of its divisors is an integer number (10500005545).

Almost surely, 2^21000011089 is an apocalyptic number.

It is an amenable number.

21000011089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000011089 is an equidigital number, since it uses as much as digits as its factorization.

21000011089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 21000011089 in words is "twenty-one billion, eleven thousand, eighty-nine".