21905026579 has 2 divisors, whose sum is σ = 21905026580. Its totient is φ = 21905026578.

The previous prime is 21905026523. The next prime is 21905026597. The reversal of 21905026579 is 97562050912.

Together with next prime (21905026597) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21905026579 - 2²¹ = 21902929427 is a prime.

It is not a weakly prime, because it can be changed into another prime (21905026079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10952513289 + 10952513290.

It is an arithmetic number, because the mean of its divisors is an integer number (10952513290).

Almost surely, 2^21905026579 is an apocalyptic number.

21905026579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21905026579 is an equidigital number, since it uses as much as digits as its factorization.

21905026579 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 340200, while the sum is 46.

The spelling of 21905026579 in words is "twenty-one billion, nine hundred five million, twenty-six thousand, five hundred seventy-nine".