256718668 has 12 divisors (see below), whose sum is σ = 454671000. Its totient is φ = 126812672.

The previous prime is 256718659. The next prime is 256718677. The reversal of 256718668 is 866817652.

It is an interprime number because it is at equal distance from previous prime (256718659) and next prime (256718677).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 386293 + ... + 386956.

It is an arithmetic number, because the mean of its divisors is an integer number (37889250).

Almost surely, 2^256718668 is an apocalyptic number.

It is an amenable number.

256718668 is a deficient number, since it is larger than the sum of its proper divisors (197952332).

256718668 is a wasteful number, since it uses less digits than its factorization.

256718668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773336 (or 773334 counting only the distinct ones).

The product of its digits is 967680, while the sum is 49.

The square root of 256718668 is about 16022.4426352538. The cubic root of 256718668 is about 635.5540397801.

The spelling of 256718668 in words is "two hundred fifty-six million, seven hundred eighteen thousand, six hundred sixty-eight".