18218504 has 32 divisors (see below), whose sum is σ = 35693400. Its totient is φ = 8709120.

The previous prime is 18218491. The next prime is 18218513. The reversal of 18218504 is 40581281.

It can be written as a sum of positive squares in 4 ways, for example, as 12974404 + 5244100 = 3602^2 + 2290^2 .

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17552 + ... + 18560.

Almost surely, 2^18218504 is an apocalyptic number.

It is an amenable number.

18218504 is a deficient number, since it is larger than the sum of its proper divisors (17474896).

18218504 is a wasteful number, since it uses less digits than its factorization.

18218504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1113 (or 1109 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 18218504 is about 4268.3139528390. The cubic root of 18218504 is about 263.1303261899.

Adding to 18218504 its reverse (40581281), we get a palindrome (58799785).

The spelling of 18218504 in words is "eighteen million, two hundred eighteen thousand, five hundred four".