256166666 has 8 divisors (see below), whose sum is σ = 439142880. Its totient is φ = 109785708.

The previous prime is 256166639. The next prime is 256166681. The reversal of 256166666 is 666661652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon 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, 9148796 + ... + 9148823.

It is an arithmetic number, because the mean of its divisors is an integer number (54892860).

Almost surely, 2^256166666 is an apocalyptic number.

256166666 is a deficient number, since it is larger than the sum of its proper divisors (182976214).

256166666 is a wasteful number, since it uses less digits than its factorization.

256166666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18297628.

The product of its digits is 466560, while the sum is 44.

The square root of 256166666 is about 16005.2074650721. The cubic root of 256166666 is about 635.0981855739.

The spelling of 256166666 in words is "two hundred fifty-six million, one hundred sixty-six thousand, six hundred sixty-six".