18189647161 has 9 divisors (see below), whose sum is σ = 21160483749. Its totient is φ = 15590316924.

The previous prime is 18189647153. The next prime is 18189647167. The reversal of 18189647161 is 16174698181.

The square root of 18189647161 is 134869.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 18189647161 - 2³ = 18189647153 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18189647099 and 18189647108.

It is not an unprimeable number, because it can be changed into a prime (18189647167) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 934450 + ... + 953716.

It is an arithmetic number, because the mean of its divisors is an integer number (2351164861).

Almost surely, 2^18189647161 is an apocalyptic number.

18189647161 is the 134869-th square number.

18189647161 is the 67435-th centered octagonal number.

It is an amenable number.

18189647161 is a deficient number, since it is larger than the sum of its proper divisors (2970836588).

18189647161 is an frugal number, since it uses more digits than its factorization.

18189647161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38548 (or 19274 counting only the distinct ones).

The product of its digits is 580608, while the sum is 52.

The spelling of 18189647161 in words is "eighteen billion, one hundred eighty-nine million, six hundred forty-seven thousand, one hundred sixty-one".