21110030309 has 2 divisors, whose sum is σ = 21110030310. Its totient is φ = 21110030308.

The previous prime is 21110030287. The next prime is 21110030317. The reversal of 21110030309 is 90303001112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19865493025 + 1244537284 = 140945^2 + 35278^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110030309 - 2¹⁶ = 21109964773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21110030369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555015154 + 10555015155.

It is an arithmetic number, because the mean of its divisors is an integer number (10555015155).

Almost surely, 2^21110030309 is an apocalyptic number.

It is an amenable number.

21110030309 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110030309 is an equidigital number, since it uses as much as digits as its factorization.

21110030309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The spelling of 21110030309 in words is "twenty-one billion, one hundred ten million, thirty thousand, three hundred nine".