18520208 has 80 divisors (see below), whose sum is σ = 44354304. Its totient is φ = 7311360.

The previous prime is 18520199. The next prime is 18520213. The reversal of 18520208 is 80202581.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135116 + ... + 135252.

Almost surely, 2^18520208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18520208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22177152).

18520208 is an abundant number, since it is smaller than the sum of its proper divisors (25834096).

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

18520208 is a wasteful number, since it uses less digits than its factorization.

18520208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 26.

The square root of 18520208 is about 4303.5111246516. The cubic root of 18520208 is about 264.5748874041.

Adding to 18520208 its reverse (80202581), we get a palindrome (98722789).

The spelling of 18520208 in words is "eighteen million, five hundred twenty thousand, two hundred eight".