21095222879 has 2 divisors, whose sum is σ = 21095222880. Its totient is φ = 21095222878.

The previous prime is 21095222857. The next prime is 21095222881. The reversal of 21095222879 is 97822259012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21095222879 - 2³² = 16800255583 is a prime.

Together with 21095222881, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21095222839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10547611439 + 10547611440.

It is an arithmetic number, because the mean of its divisors is an integer number (10547611440).

Almost surely, 2^21095222879 is an apocalyptic number.

21095222879 is a deficient number, since it is larger than the sum of its proper divisors (1).

21095222879 is an equidigital number, since it uses as much as digits as its factorization.

21095222879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 47.

The spelling of 21095222879 in words is "twenty-one billion, ninety-five million, two hundred twenty-two thousand, eight hundred seventy-nine".