21010866903473 has 2 divisors, whose sum is σ = 21010866903474. Its totient is φ = 21010866903472.

The previous prime is 21010866903469. The next prime is 21010866903511. The reversal of 21010866903473 is 37430966801012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19106488983409 + 1904377920064 = 4371097^2 + 1379992^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010866903473 - 2² = 21010866903469 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010866903413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505433451736 + 10505433451737.

It is an arithmetic number, because the mean of its divisors is an integer number (10505433451737).

Almost surely, 2^{21010866903473} is an apocalyptic number.

It is an amenable number.

21010866903473 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010866903473 is an equidigital number, since it uses as much as digits as its factorization.

21010866903473 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1306368, while the sum is 50.

The spelling of 21010866903473 in words is "twenty-one trillion, ten billion, eight hundred sixty-six million, nine hundred three thousand, four hundred seventy-three".