181808 has 20 divisors (see below), whose sum is σ = 384648. Its totient is φ = 82560.

The previous prime is 181789. The next prime is 181813. The reversal of 181808 is 808181.

It is an unprimeable number.

181808 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 341 + ... + 692.

2¹⁸¹⁸⁰⁸ is an apocalyptic number.

It is an amenable number.

181808 is an abundant number, since it is smaller than the sum of its proper divisors (202840).

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

181808 is a wasteful number, since it uses less digits than its factorization.

181808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1052 (or 1046 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 181808 is about 426.3894933040. The cubic root of 181808 is about 56.6505759774.

Adding to 181808 its reverse (808181), we get a palindrome (989989).

It can be divided in two parts, 181 and 808, that added together give a palindrome (989).

The spelling of 181808 in words is "one hundred eighty-one thousand, eight hundred eight".