18185872 has 10 divisors (see below), whose sum is σ = 35235158. Its totient is φ = 9092928.

The previous prime is 18185821. The next prime is 18185891. The reversal of 18185872 is 27858181.

It can be written as a sum of positive squares in only one way, i.e., 15241216 + 2944656 = 3904^2 + 1716^2 .

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 568293 + ... + 568324.

Almost surely, 2^18185872 is an apocalyptic number.

It is an amenable number.

18185872 is a deficient number, since it is larger than the sum of its proper divisors (17049286).

18185872 is a wasteful number, since it uses less digits than its factorization.

18185872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1136625 (or 1136619 counting only the distinct ones).

The product of its digits is 35840, while the sum is 40.

The square root of 18185872 is about 4264.4896529362. The cubic root of 18185872 is about 262.9731306915.

The spelling of 18185872 in words is "eighteen million, one hundred eighty-five thousand, eight hundred seventy-two".