66081808 has 20 divisors (see below), whose sum is σ = 137882668. Its totient is φ = 30499200.

The previous prime is 66081803. The next prime is 66081811. The reversal of 66081808 is 80818066.

It can be written as a sum of positive squares in 2 ways, for example, as 10549504 + 55532304 = 3248^2 + 7452^2 .

It is not an unprimeable number, because it can be changed into a prime (66081803) 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, 158643 + ... + 159058.

Almost surely, 2^66081808 is an apocalyptic number.

It is an amenable number.

66081808 is an abundant number, since it is smaller than the sum of its proper divisors (71800860).

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

66081808 is a wasteful number, since it uses less digits than its factorization.

66081808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317722 (or 317716 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 37.

The square root of 66081808 is about 8129.0717797298. The cubic root of 66081808 is about 404.2909057292.

The spelling of 66081808 in words is "sixty-six million, eighty-one thousand, eight hundred eight".