16559521309 has 2 divisors, whose sum is σ = 16559521310. Its totient is φ = 16559521308.

The previous prime is 16559521271. The next prime is 16559521367. The reversal of 16559521309 is 90312595561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9258673284 + 7300848025 = 96222^2 + 85445^2 .

It is a cyclic number.

It is not a de Polignac number, because 16559521309 - 2⁹ = 16559520797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16559321309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8279760654 + 8279760655.

It is an arithmetic number, because the mean of its divisors is an integer number (8279760655).

Almost surely, 2^16559521309 is an apocalyptic number.

It is an amenable number.

16559521309 is a deficient number, since it is larger than the sum of its proper divisors (1).

16559521309 is an equidigital number, since it uses as much as digits as its factorization.

16559521309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 364500, while the sum is 46.

The spelling of 16559521309 in words is "sixteen billion, five hundred fifty-nine million, five hundred twenty-one thousand, three hundred nine".