21659444267 has 2 divisors, whose sum is σ = 21659444268. Its totient is φ = 21659444266.

The previous prime is 21659444251. The next prime is 21659444297. The reversal of 21659444267 is 76244495612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21659444267 - 2⁴ = 21659444251 is a prime.

It is not a weakly prime, because it can be changed into another prime (21659444237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10829722133 + 10829722134.

It is an arithmetic number, because the mean of its divisors is an integer number (10829722134).

Almost surely, 2^21659444267 is an apocalyptic number.

21659444267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21659444267 is an equidigital number, since it uses as much as digits as its factorization.

21659444267 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2903040, while the sum is 50.

The spelling of 21659444267 in words is "twenty-one billion, six hundred fifty-nine million, four hundred forty-four thousand, two hundred sixty-seven".