66581008 has 20 divisors (see below), whose sum is σ = 138924268. Its totient is φ = 30729600.

The previous prime is 66581003. The next prime is 66581017. The reversal of 66581008 is 80018566.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14047504 + 52533504 = 3748^2 + 7248^2 .

It is not an unprimeable number, because it can be changed into a prime (66581003) 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, 159843 + ... + 160258.

Almost surely, 2^66581008 is an apocalyptic number.

It is an amenable number.

66581008 is an abundant number, since it is smaller than the sum of its proper divisors (72343260).

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

66581008 is a wasteful number, since it uses less digits than its factorization.

66581008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320122 (or 320116 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 66581008 is about 8159.7186225997. The cubic root of 66581008 is about 405.3063941680.

The spelling of 66581008 in words is "sixty-six million, five hundred eighty-one thousand, eight".