21230203130209 has 2 divisors, whose sum is σ = 21230203130210. Its totient is φ = 21230203130208.

The previous prime is 21230203130057. The next prime is 21230203130231. The reversal of 21230203130209 is 90203130203212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20788383687184 + 441819443025 = 4559428^2 + 664695^2 .

It is a cyclic number.

It is not a de Polignac number, because 21230203130209 - 2²¹ = 21230201033057 is a prime.

It is not a weakly prime, because it can be changed into another prime (21230203130249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615101565104 + 10615101565105.

It is an arithmetic number, because the mean of its divisors is an integer number (10615101565105).

Almost surely, 2^{21230203130209} is an apocalyptic number.

It is an amenable number.

21230203130209 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230203130209 is an equidigital number, since it uses as much as digits as its factorization.

21230203130209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 28.

The spelling of 21230203130209 in words is "twenty-one trillion, two hundred thirty billion, two hundred three million, one hundred thirty thousand, two hundred nine".