66330640 has 40 divisors (see below), whose sum is σ = 158393880. Its totient is φ = 25814016.

The previous prime is 66330629. The next prime is 66330679. The reversal of 66330640 is 4603366.

It can be written as a sum of positive squares in 4 ways, for example, as 19927296 + 46403344 = 4464^2 + 6812^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 66330599 and 66330608.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8245 + ... + 14164.

It is an arithmetic number, because the mean of its divisors is an integer number (3959847).

Almost surely, 2^66330640 is an apocalyptic number.

It is an amenable number.

66330640 is an abundant number, since it is smaller than the sum of its proper divisors (92063240).

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

66330640 is a wasteful number, since it uses less digits than its factorization.

66330640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22459 (or 22453 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 28.

The square root of 66330640 is about 8144.3624673758. The cubic root of 66330640 is about 404.7977245259.

The spelling of 66330640 in words is "sixty-six million, three hundred thirty thousand, six hundred forty".