18122161 has 2 divisors, whose sum is σ = 18122162. Its totient is φ = 18122160.

The previous prime is 18122141. The next prime is 18122173. The reversal of 18122161 is 16122181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11771761 + 6350400 = 3431^2 + 2520^2 .

It is an emirp because it is prime and its reverse (16122181) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18122161 is a prime.

It is a Chen prime.

It is equal to p_1158601 and since 18122161 and 1158601 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (18122101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9061080 + 9061081.

It is an arithmetic number, because the mean of its divisors is an integer number (9061081).

Almost surely, 2^18122161 is an apocalyptic number.

It is an amenable number.

18122161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18122161 is an equidigital number, since it uses as much as digits as its factorization.

18122161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 192, while the sum is 22.

The square root of 18122161 is about 4257.0131547835. The cubic root of 18122161 is about 262.6656780249.

The spelling of 18122161 in words is "eighteen million, one hundred twenty-two thousand, one hundred sixty-one".