18081818 has 8 divisors (see below), whose sum is σ = 28302048. Its totient is φ = 8647804.

The previous prime is 18081781. The next prime is 18081821. The reversal of 18081818 is 81818081.

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

18081818 is a modest number, since divided by 1818 gives 1808 as remainder.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196496 + ... + 196587.

It is an arithmetic number, because the mean of its divisors is an integer number (3537756).

Almost surely, 2^18081818 is an apocalyptic number.

18081818 is a deficient number, since it is larger than the sum of its proper divisors (10220230).

18081818 is a wasteful number, since it uses less digits than its factorization.

18081818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393108.

The product of its (nonzero) digits is 4096, while the sum is 35.

The square root of 18081818 is about 4252.2720985374. The cubic root of 18081818 is about 262.4706204458.

Adding to 18081818 its reverse (81818081), we get a palindrome (99899899).

The spelling of 18081818 in words is "eighteen million, eighty-one thousand, eight hundred eighteen".