21202002001009 has 2 divisors, whose sum is σ = 21202002001010. Its totient is φ = 21202002001008.

The previous prime is 21202002001001. The next prime is 21202002001013. The reversal of 21202002001009 is 90010020020212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16912327251600 + 4289674749409 = 4112460^2 + 2071153^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202002001009 - 2³ = 21202002001001 is a prime.

It is not a weakly prime, because it can be changed into another prime (21202002001001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601001000504 + 10601001000505.

It is an arithmetic number, because the mean of its divisors is an integer number (10601001000505).

Almost surely, 2^{21202002001009} is an apocalyptic number.

It is an amenable number.

21202002001009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202002001009 is an equidigital number, since it uses as much as digits as its factorization.

21202002001009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

The spelling of 21202002001009 in words is "twenty-one trillion, two hundred two billion, two million, one thousand, nine".