256016666 has 4 divisors (see below), whose sum is σ = 384025002. Its totient is φ = 128008332.

The previous prime is 256016647. The next prime is 256016671. The reversal of 256016666 is 666610652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 146918641 + 109098025 = 12121^2 + 10445^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64004165 + ... + 64004168.

Almost surely, 2^256016666 is an apocalyptic number.

256016666 is a deficient number, since it is larger than the sum of its proper divisors (128008336).

256016666 is a wasteful number, since it uses less digits than its factorization.

256016666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128008335.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 256016666 is about 16000.5208040238. The cubic root of 256016666 is about 634.9741994601.

The spelling of 256016666 in words is "two hundred fifty-six million, sixteen thousand, six hundred sixty-six".