20081808 has 30 divisors (see below), whose sum is σ = 56201574. Its totient is φ = 6693888.

The previous prime is 20081797. The next prime is 20081821. The reversal of 20081808 is 80818002.

It can be written as a sum of positive squares in only one way, i.e., 14379264 + 5702544 = 3792^2 + 2388^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 69585 + ... + 69872.

Almost surely, 2^20081808 is an apocalyptic number.

It is an amenable number.

20081808 is an abundant number, since it is smaller than the sum of its proper divisors (36119766).

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

20081808 is a wasteful number, since it uses less digits than its factorization.

20081808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139471 (or 139462 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 20081808 is about 4481.2730334136. The cubic root of 20081808 is about 271.8113599756.

The spelling of 20081808 in words is "twenty million, eighty-one thousand, eight hundred eight".