18081317 has 4 divisors (see below), whose sum is σ = 18387840. Its totient is φ = 17774796.

The previous prime is 18081313. The next prime is 18081337. The reversal of 18081317 is 71318081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71318081 = 281 ⋅253801.

It is a cyclic number.

It is not a de Polignac number, because 18081317 - 2² = 18081313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18081317.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18081311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153173 + ... + 153290.

It is an arithmetic number, because the mean of its divisors is an integer number (4596960).

Almost surely, 2^18081317 is an apocalyptic number.

It is an amenable number.

18081317 is a deficient number, since it is larger than the sum of its proper divisors (306523).

18081317 is an equidigital number, since it uses as much as digits as its factorization.

18081317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306522.

The product of its (nonzero) digits is 1344, while the sum is 29.

The square root of 18081317 is about 4252.2131884467. The cubic root of 18081317 is about 262.4681962981.

Adding to 18081317 its reverse (71318081), we get a palindrome (89399398).

It can be divided in two parts, 1808 and 1317, that added together give a 5-th power (3125 = 5⁵).

The spelling of 18081317 in words is "eighteen million, eighty-one thousand, three hundred seventeen".