18081218 has 8 divisors (see below), whose sum is σ = 27448848. Its totient is φ = 8931604.

The previous prime is 18081211. The next prime is 18081221. The reversal of 18081218 is 81218081.

18081218 = 1222² + 1223² + ... + 1233².

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 (18081211) 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, 54296 + ... + 54627.

It is an arithmetic number, because the mean of its divisors is an integer number (3431106).

Almost surely, 2^18081218 is an apocalyptic number.

18081218 is a deficient number, since it is larger than the sum of its proper divisors (9367630).

18081218 is a wasteful number, since it uses less digits than its factorization.

18081218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109008.

The product of its (nonzero) digits is 1024, while the sum is 29.

The square root of 18081218 is about 4252.2015474340. The cubic root of 18081218 is about 262.4677172696.

Adding to 18081218 its reverse (81218081), we get a palindrome (99299299).

The spelling of 18081218 in words is "eighteen million, eighty-one thousand, two hundred eighteen".