21010430009 has 2 divisors, whose sum is σ = 21010430010. Its totient is φ = 21010430008.

The previous prime is 21010429991. The next prime is 21010430059. The reversal of 21010430009 is 90003401012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16837657600 + 4172772409 = 129760^2 + 64597^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010430009 - 2²⁴ = 20993652793 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010430059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505215004 + 10505215005.

It is an arithmetic number, because the mean of its divisors is an integer number (10505215005).

Almost surely, 2^21010430009 is an apocalyptic number.

It is an amenable number.

21010430009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010430009 is an equidigital number, since it uses as much as digits as its factorization.

21010430009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The spelling of 21010430009 in words is "twenty-one billion, ten million, four hundred thirty thousand, nine".