66390256 has 20 divisors (see below), whose sum is σ = 135401800. Its totient is φ = 31447872.

The previous prime is 66390239. The next prime is 66390271. The reversal of 66390256 is 65209366.

66390256 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 108891 + ... + 109498.

It is an arithmetic number, because the mean of its divisors is an integer number (6770090).

Almost surely, 2^66390256 is an apocalyptic number.

It is an amenable number.

66390256 is an abundant number, since it is smaller than the sum of its proper divisors (69011544).

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

66390256 is a wasteful number, since it uses less digits than its factorization.

66390256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218416 (or 218410 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 37.

The square root of 66390256 is about 8148.0216003641. The cubic root of 66390256 is about 404.9189615838.

The spelling of 66390256 in words is "sixty-six million, three hundred ninety thousand, two hundred fifty-six".