18142217 has 2 divisors, whose sum is σ = 18142218. Its totient is φ = 18142216.

The previous prime is 18142199. The next prime is 18142219. The reversal of 18142217 is 71224181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18139081 + 3136 = 4259^2 + 56^2 .

It is a cyclic number.

It is not a de Polignac number, because 18142217 - 2¹² = 18138121 is a prime.

Together with 18142219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18142219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9071108 + 9071109.

It is an arithmetic number, because the mean of its divisors is an integer number (9071109).

Almost surely, 2^18142217 is an apocalyptic number.

It is an amenable number.

18142217 is a deficient number, since it is larger than the sum of its proper divisors (1).

18142217 is an equidigital number, since it uses as much as digits as its factorization.

18142217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 896, while the sum is 26.

The square root of 18142217 is about 4259.3681456291. The cubic root of 18142217 is about 262.7625406569.

Adding to 18142217 its reverse (71224181), we get a palindrome (89366398).

The spelling of 18142217 in words is "eighteen million, one hundred forty-two thousand, two hundred seventeen".