8159639561 has 2 divisors, whose sum is σ = 8159639562. Its totient is φ = 8159639560.

The previous prime is 8159639557. The next prime is 8159639599. The reversal of 8159639561 is 1659369518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7982350336 + 177289225 = 89344^2 + 13315^2 .

It is a cyclic number.

It is not a de Polignac number, because 8159639561 - 2² = 8159639557 is a prime.

It is not a weakly prime, because it can be changed into another prime (8159639531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4079819780 + 4079819781.

It is an arithmetic number, because the mean of its divisors is an integer number (4079819781).

Almost surely, 2^8159639561 is an apocalyptic number.

It is an amenable number.

8159639561 is a deficient number, since it is larger than the sum of its proper divisors (1).

8159639561 is an equidigital number, since it uses as much as digits as its factorization.

8159639561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1749600, while the sum is 53.

The square root of 8159639561 is about 90330.7232396597. The cubic root of 8159639561 is about 2013.2157760299.

The spelling of 8159639561 in words is "eight billion, one hundred fifty-nine million, six hundred thirty-nine thousand, five hundred sixty-one".