18564418 has 4 divisors (see below), whose sum is σ = 27846630. Its totient is φ = 9282208.

The previous prime is 18564407. The next prime is 18564439. The reversal of 18564418 is 81446581.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81446581 = 107 ⋅761183.

It can be written as a sum of positive squares in only one way, i.e., 15547249 + 3017169 = 3943^2 + 1737^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4641103 + ... + 4641106.

Almost surely, 2^18564418 is an apocalyptic number.

18564418 is a deficient number, since it is larger than the sum of its proper divisors (9282212).

18564418 is an equidigital number, since it uses as much as digits as its factorization.

18564418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9282211.

The product of its digits is 30720, while the sum is 37.

The square root of 18564418 is about 4308.6445664501. The cubic root of 18564418 is about 264.7852443076.

The spelling of 18564418 in words is "eighteen million, five hundred sixty-four thousand, four hundred eighteen".