21010866903469 has 2 divisors, whose sum is σ = 21010866903470. Its totient is φ = 21010866903468.

The previous prime is 21010866903451. The next prime is 21010866903473. The reversal of 21010866903469 is 96430966801012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13187864880100 + 7823002023369 = 3631510^2 + 2796963^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010866903469 - 2⁴¹ = 18811843647917 is a prime.

It is a super-2 number, since 2×21010866903469² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21010866903769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505433451734 + 10505433451735.

It is an arithmetic number, because the mean of its divisors is an integer number (10505433451735).

Almost surely, 2^{21010866903469} is an apocalyptic number.

It is an amenable number.

21010866903469 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010866903469 is an equidigital number, since it uses as much as digits as its factorization.

21010866903469 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3359232, while the sum is 55.

The spelling of 21010866903469 in words is "twenty-one trillion, ten billion, eight hundred sixty-six million, nine hundred three thousand, four hundred sixty-nine".