18189916 has 24 divisors (see below), whose sum is σ = 33989760. Its totient is φ = 8492400.

The previous prime is 18189889. The next prime is 18189917. The reversal of 18189916 is 61998181.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18189917) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3711 + ... + 7081.

It is an arithmetic number, because the mean of its divisors is an integer number (1416240).

Almost surely, 2^18189916 is an apocalyptic number.

It is an amenable number.

18189916 is a deficient number, since it is larger than the sum of its proper divisors (15799844).

18189916 is a wasteful number, since it uses less digits than its factorization.

18189916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3465 (or 3463 counting only the distinct ones).

The product of its digits is 31104, while the sum is 43.

The square root of 18189916 is about 4264.9637747582. The cubic root of 18189916 is about 262.9926217287.

The spelling of 18189916 in words is "eighteen million, one hundred eighty-nine thousand, nine hundred sixteen".