8549219561 has 2 divisors, whose sum is σ = 8549219562. Its totient is φ = 8549219560.

The previous prime is 8549219543. The next prime is 8549219579. The reversal of 8549219561 is 1659129458.

8549219561 = 65380² + 65381².

It is a balanced prime because it is at equal distance from previous prime (8549219543) and next prime (8549219579).

It can be written as a sum of positive squares in only one way, i.e., 4274675161 + 4274544400 = 65381^2 + 65380^2 .

It is a cyclic number.

It is not a de Polignac number, because 8549219561 - 2¹⁴ = 8549203177 is a prime.

It is not a weakly prime, because it can be changed into another prime (8549239561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4274609780 + 4274609781.

It is an arithmetic number, because the mean of its divisors is an integer number (4274609781).

Almost surely, 2^8549219561 is an apocalyptic number.

8549219561 is the 65381-st centered square number.

It is an amenable number.

8549219561 is a deficient number, since it is larger than the sum of its proper divisors (1).

8549219561 is an equidigital number, since it uses as much as digits as its factorization.

8549219561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 777600, while the sum is 50.

The square root of 8549219561 is about 92461.9898174380. The cubic root of 8549219561 is about 2044.7591342379.

The spelling of 8549219561 in words is "eight billion, five hundred forty-nine million, two hundred nineteen thousand, five hundred sixty-one".