18618818 has 8 divisors (see below), whose sum is σ = 27979020. Its totient is φ = 9292480.

The previous prime is 18618811. The next prime is 18618857. The reversal of 18618818 is 81881681.

It can be written as a sum of positive squares in 2 ways, for example, as 17530969 + 1087849 = 4187^2 + 1043^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18618811) 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, 7043 + ... + 9318.

Almost surely, 2^18618818 is an apocalyptic number.

18618818 is a deficient number, since it is larger than the sum of its proper divisors (9360202).

18618818 is a wasteful number, since it uses less digits than its factorization.

18618818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16932.

The product of its digits is 24576, while the sum is 41.

The square root of 18618818 is about 4314.9528386762. The cubic root of 18618818 is about 265.0436287488.

The spelling of 18618818 in words is "eighteen million, six hundred eighteen thousand, eight hundred eighteen".