18008194 has 4 divisors (see below), whose sum is σ = 27012294. Its totient is φ = 9004096.

The previous prime is 18008189. The next prime is 18008197. The reversal of 18008194 is 49180081.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17347225 + 660969 = 4165^2 + 813^2 .

It is a super-2 number, since 2×18008194² = 648590102283272, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18008197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4502047 + ... + 4502050.

Almost surely, 2^18008194 is an apocalyptic number.

18008194 is a deficient number, since it is larger than the sum of its proper divisors (9004100).

18008194 is an equidigital number, since it uses as much as digits as its factorization.

18008194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9004099.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 18008194 is about 4243.6062494063. The cubic root of 18008194 is about 262.1139007121.

The spelling of 18008194 in words is "eighteen million, eight thousand, one hundred ninety-four".