18162217 has 2 divisors, whose sum is σ = 18162218. Its totient is φ = 18162216.

The previous prime is 18162173. The next prime is 18162259. The reversal of 18162217 is 71226181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17673616 + 488601 = 4204^2 + 699^2 .

It is a cyclic number.

It is not a de Polignac number, because 18162217 - 2¹¹ = 18160169 is a prime.

It is a super-2 number, since 2×18162217² = 659732252710178, which contains 22 as substring.

It is equal to p_1160983 and since 18162217 and 1160983 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 (18162317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9081108 + 9081109.

It is an arithmetic number, because the mean of its divisors is an integer number (9081109).

Almost surely, 2^18162217 is an apocalyptic number.

It is an amenable number.

18162217 is a deficient number, since it is larger than the sum of its proper divisors (1).

18162217 is an equidigital number, since it uses as much as digits as its factorization.

18162217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1344, while the sum is 28.

The square root of 18162217 is about 4261.7152650077. The cubic root of 18162217 is about 262.8590617687.

Adding to 18162217 its reverse (71226181), we get a palindrome (89388398).

The spelling of 18162217 in words is "eighteen million, one hundred sixty-two thousand, two hundred seventeen".