18240161 has 2 divisors, whose sum is σ = 18240162. Its totient is φ = 18240160.

The previous prime is 18240151. The next prime is 18240179. The reversal of 18240161 is 16104281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16120225 + 2119936 = 4015^2 + 1456^2 .

It is an emirp because it is prime and its reverse (16104281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18240161 - 2⁶ = 18240097 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18240151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9120080 + 9120081.

It is an arithmetic number, because the mean of its divisors is an integer number (9120081).

Almost surely, 2^18240161 is an apocalyptic number.

It is an amenable number.

18240161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18240161 is an equidigital number, since it uses as much as digits as its factorization.

18240161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 18240161 is about 4270.8501495604. The cubic root of 18240161 is about 263.2345491073.

The spelling of 18240161 in words is "eighteen million, two hundred forty thousand, one hundred sixty-one".