66407688 has 40 divisors (see below), whose sum is σ = 186004830. Its totient is φ = 22135680.

The previous prime is 66407687. The next prime is 66407701. The reversal of 66407688 is 88670466.

It is a happy number.

66407688 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 only one way, i.e., 35070084 + 31337604 = 5922^2 + 5598^2 .

It is not an unprimeable number, because it can be changed into a prime (66407681) 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 9 ways as a sum of consecutive naturals, for example, 50593 + ... + 51888.

Almost surely, 2^66407688 is an apocalyptic number.

It is an amenable number.

66407688 is an abundant number, since it is smaller than the sum of its proper divisors (119597142).

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

66407688 is a wasteful number, since it uses less digits than its factorization.

66407688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102499 (or 102486 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 66407688 is about 8149.0912376780. The cubic root of 66407688 is about 404.9543981577.

The spelling of 66407688 in words is "sixty-six million, four hundred seven thousand, six hundred eighty-eight".