66400308 has 72 divisors (see below), whose sum is σ = 184235688. Its totient is φ = 20037888.

The previous prime is 66400303. The next prime is 66400309. The reversal of 66400308 is 80300466.

66400308 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 10404 + 66389904 = 102^2 + 8148^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66400303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23466 + ... + 26142.

It is an arithmetic number, because the mean of its divisors is an integer number (2558829).

Almost surely, 2^66400308 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 66400308, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92117844).

66400308 is an abundant number, since it is smaller than the sum of its proper divisors (117835380).

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

66400308 is a wasteful number, since it uses less digits than its factorization.

66400308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2753 (or 2748 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 66400308 is about 8148.6384138701. The cubic root of 66400308 is about 404.9393965103.

The spelling of 66400308 in words is "sixty-six million, four hundred thousand, three hundred eight".