18509016 has 16 divisors (see below), whose sum is σ = 46272600. Its totient is φ = 6169664.

The previous prime is 18509011. The next prime is 18509033. The reversal of 18509016 is 61090581.

It is a happy number.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18509011) 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, 385581 + ... + 385628.

Almost surely, 2^18509016 is an apocalyptic number.

It is an amenable number.

18509016 is an abundant number, since it is smaller than the sum of its proper divisors (27763584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18509016 is a wasteful number, since it uses less digits than its factorization.

18509016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 771218 (or 771214 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 30.

The square root of 18509016 is about 4302.2105945665. The cubic root of 18509016 is about 264.5215813285.

Adding to 18509016 its reverse (61090581), we get a palindrome (79599597).

The spelling of 18509016 in words is "eighteen million, five hundred nine thousand, sixteen".