21010866903511 has 2 divisors, whose sum is σ = 21010866903512. Its totient is φ = 21010866903510.

The previous prime is 21010866903473. The next prime is 21010866903541. The reversal of 21010866903511 is 11530966801012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21010866903511 - 2¹⁵ = 21010866870743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21010866903541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505433451755 + 10505433451756.

It is an arithmetic number, because the mean of its divisors is an integer number (10505433451756).

Almost surely, 2^{21010866903511} is an apocalyptic number.

21010866903511 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010866903511 is an equidigital number, since it uses as much as digits as its factorization.

21010866903511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 43.

The spelling of 21010866903511 in words is "twenty-one trillion, ten billion, eight hundred sixty-six million, nine hundred three thousand, five hundred eleven".