18456161 has 2 divisors, whose sum is σ = 18456162. Its totient is φ = 18456160.

The previous prime is 18456157. The next prime is 18456181. The reversal of 18456161 is 16165481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15358561 + 3097600 = 3919^2 + 1760^2 .

It is a cyclic number.

It is not a de Polignac number, because 18456161 - 2² = 18456157 is a prime.

It is not a weakly prime, because it can be changed into another prime (18456121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9228080 + 9228081.

It is an arithmetic number, because the mean of its divisors is an integer number (9228081).

Almost surely, 2^18456161 is an apocalyptic number.

It is an amenable number.

18456161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18456161 is an equidigital number, since it uses as much as digits as its factorization.

18456161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 32.

The square root of 18456161 is about 4296.0634306304. The cubic root of 18456161 is about 264.2695488808.

The spelling of 18456161 in words is "eighteen million, four hundred fifty-six thousand, one hundred sixty-one".