9161143661 has 2 divisors, whose sum is σ = 9161143662. Its totient is φ = 9161143660.

The previous prime is 9161143643. The next prime is 9161143699. The reversal of 9161143661 is 1663411619.

9161143661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (9161143699) can be obtained adding 9161143661 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7432164100 + 1728979561 = 86210^2 + 41581^2 .

It is a cyclic number.

It is not a de Polignac number, because 9161143661 - 2¹⁰ = 9161142637 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9161143631) 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, 4580571830 + 4580571831.

It is an arithmetic number, because the mean of its divisors is an integer number (4580571831).

Almost surely, 2^9161143661 is an apocalyptic number.

It is an amenable number.

9161143661 is a deficient number, since it is larger than the sum of its proper divisors (1).

9161143661 is an equidigital number, since it uses as much as digits as its factorization.

9161143661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 38.

The square root of 9161143661 is about 95713.8634733757. The cubic root of 9161143661 is about 2092.4249884064.

The spelling of 9161143661 in words is "nine billion, one hundred sixty-one million, one hundred forty-three thousand, six hundred sixty-one".