18615161 has 2 divisors, whose sum is σ = 18615162. Its totient is φ = 18615160.

The previous prime is 18615143. The next prime is 18615167. The reversal of 18615161 is 16151681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17472400 + 1142761 = 4180^2 + 1069^2 .

It is a cyclic number.

It is not a de Polignac number, because 18615161 - 2¹⁸ = 18353017 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18615167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9307580 + 9307581.

It is an arithmetic number, because the mean of its divisors is an integer number (9307581).

Almost surely, 2^18615161 is an apocalyptic number.

It is an amenable number.

18615161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18615161 is an equidigital number, since it uses as much as digits as its factorization.

18615161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 29.

The square root of 18615161 is about 4314.5290588893. The cubic root of 18615161 is about 265.0262748363.

The spelling of 18615161 in words is "eighteen million, six hundred fifteen thousand, one hundred sixty-one".