18280217 has 2 divisors, whose sum is σ = 18280218. Its totient is φ = 18280216.

The previous prime is 18280189. The next prime is 18280231. The reversal of 18280217 is 71208281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16289296 + 1990921 = 4036^2 + 1411^2 .

It is a cyclic number.

It is not a de Polignac number, because 18280217 - 2¹² = 18276121 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18280217.

It is not a weakly prime, because it can be changed into another prime (18280247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9140108 + 9140109.

It is an arithmetic number, because the mean of its divisors is an integer number (9140109).

Almost surely, 2^18280217 is an apocalyptic number.

It is an amenable number.

18280217 is a deficient number, since it is larger than the sum of its proper divisors (1).

18280217 is an equidigital number, since it uses as much as digits as its factorization.

18280217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 18280217 is about 4275.5370422907. The cubic root of 18280217 is about 263.4270988348.

Adding to 18280217 its reverse (71208281), we get a palindrome (89488498).

The spelling of 18280217 in words is "eighteen million, two hundred eighty thousand, two hundred seventeen".