18345517 has 2 divisors, whose sum is σ = 18345518. Its totient is φ = 18345516.

The previous prime is 18345479. The next prime is 18345527. The reversal of 18345517 is 71554381.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18096516 + 249001 = 4254^2 + 499^2 .

It is a cyclic number.

It is not a de Polignac number, because 18345517 - 2⁷ = 18345389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18345527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9172758 + 9172759.

It is an arithmetic number, because the mean of its divisors is an integer number (9172759).

Almost surely, 2^18345517 is an apocalyptic number.

It is an amenable number.

18345517 is a deficient number, since it is larger than the sum of its proper divisors (1).

18345517 is an equidigital number, since it uses as much as digits as its factorization.

18345517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16800, while the sum is 34.

The square root of 18345517 is about 4283.1667023360. The cubic root of 18345517 is about 263.7403946698.

Adding to 18345517 its reverse (71554381), we get a palindrome (89899898).

The spelling of 18345517 in words is "eighteen million, three hundred forty-five thousand, five hundred seventeen".