21828509579 has 2 divisors, whose sum is σ = 21828509580. Its totient is φ = 21828509578.

The previous prime is 21828509561. The next prime is 21828509581. The reversal of 21828509579 is 97590582812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21828509579 is a prime.

Together with 21828509581, 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 (21828509179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10914254789 + 10914254790.

It is an arithmetic number, because the mean of its divisors is an integer number (10914254790).

Almost surely, 2^21828509579 is an apocalyptic number.

21828509579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21828509579 is an equidigital number, since it uses as much as digits as its factorization.

21828509579 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3628800, while the sum is 56.

The spelling of 21828509579 in words is "twenty-one billion, eight hundred twenty-eight million, five hundred nine thousand, five hundred seventy-nine".