21828649489 has 2 divisors, whose sum is σ = 21828649490. Its totient is φ = 21828649488.

The previous prime is 21828649487. The next prime is 21828649511. The reversal of 21828649489 is 98494682812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21736489489 + 92160000 = 147433^2 + 9600^2 .

It is a cyclic number.

It is not a de Polignac number, because 21828649489 - 2¹ = 21828649487 is a prime.

It is a super-2 number, since 2×21828649489² (a number of 21 digits) contains 22 as substring.

Together with 21828649487, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21828649487) 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, 10914324744 + 10914324745.

It is an arithmetic number, because the mean of its divisors is an integer number (10914324745).

Almost surely, 2^21828649489 is an apocalyptic number.

It is an amenable number.

21828649489 is a deficient number, since it is larger than the sum of its proper divisors (1).

21828649489 is an equidigital number, since it uses as much as digits as its factorization.

21828649489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15925248, while the sum is 61.

The spelling of 21828649489 in words is "twenty-one billion, eight hundred twenty-eight million, six hundred forty-nine thousand, four hundred eighty-nine".