21092911571 has 2 divisors, whose sum is σ = 21092911572. Its totient is φ = 21092911570.

The previous prime is 21092911529. The next prime is 21092911573. The reversal of 21092911571 is 17511929012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21092911571 is a prime.

It is a Sophie Germain prime.

Together with 21092911573, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21092911573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10546455785 + 10546455786.

It is an arithmetic number, because the mean of its divisors is an integer number (10546455786).

Almost surely, 2^21092911571 is an apocalyptic number.

21092911571 is a deficient number, since it is larger than the sum of its proper divisors (1).

21092911571 is an equidigital number, since it uses as much as digits as its factorization.

21092911571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11340, while the sum is 38.

The spelling of 21092911571 in words is "twenty-one billion, ninety-two million, nine hundred eleven thousand, five hundred seventy-one".