18171161 has 2 divisors, whose sum is σ = 18171162. Its totient is φ = 18171160.

The previous prime is 18171149. The next prime is 18171169. The reversal of 18171161 is 16117181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11095561 + 7075600 = 3331^2 + 2660^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18171161 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18171161.

It is not a weakly prime, because it can be changed into another prime (18171169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9085580 + 9085581.

It is an arithmetic number, because the mean of its divisors is an integer number (9085581).

Almost surely, 2^18171161 is an apocalyptic number.

It is an amenable number.

18171161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18171161 is an equidigital number, since it uses as much as digits as its factorization.

18171161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336, while the sum is 26.

The square root of 18171161 is about 4262.7644785984. The cubic root of 18171161 is about 262.9022030811.

The spelling of 18171161 in words is "eighteen million, one hundred seventy-one thousand, one hundred sixty-one".