18518117 has 8 divisors (see below), whose sum is σ = 19650456. Its totient is φ = 17390592.

The previous prime is 18518113. The next prime is 18518161. The reversal of 18518117 is 71181581.

It can be written as a sum of positive squares in 4 ways, for example, as 591361 + 17926756 = 769^2 + 4234^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18518117 - 2² = 18518113 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18518113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9533 + ... + 11309.

It is an arithmetic number, because the mean of its divisors is an integer number (2456307).

Almost surely, 2^18518117 is an apocalyptic number.

18518117 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18518117 is a deficient number, since it is larger than the sum of its proper divisors (1132339).

18518117 is a wasteful number, since it uses less digits than its factorization.

18518117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2407.

The product of its digits is 2240, while the sum is 32.

The square root of 18518117 is about 4303.2681766304. The cubic root of 18518117 is about 264.5649298681.

Adding to 18518117 its reverse (71181581), we get a palindrome (89699698).

The spelling of 18518117 in words is "eighteen million, five hundred eighteen thousand, one hundred seventeen".