18681117 has 32 divisors (see below), whose sum is σ = 31422720. Its totient is φ = 9607680.

The previous prime is 18681053. The next prime is 18681139. The reversal of 18681117 is 71118681.

It is not a de Polignac number, because 18681117 - 2⁶ = 18681053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18681167) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10359 + ... + 12027.

It is an arithmetic number, because the mean of its divisors is an integer number (981960).

Almost surely, 2^18681117 is an apocalyptic number.

It is an amenable number.

18681117 is a deficient number, since it is larger than the sum of its proper divisors (12741603).

18681117 is a wasteful number, since it uses less digits than its factorization.

18681117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1733.

The product of its digits is 2688, while the sum is 33.

The square root of 18681117 is about 4322.1657765523. The cubic root of 18681117 is about 265.3389137078.

Adding to 18681117 its reverse (71118681), we get a palindrome (89799798).

The spelling of 18681117 in words is "eighteen million, six hundred eighty-one thousand, one hundred seventeen".