864256681 has 4 divisors (see below), whose sum is σ = 864764100. Its totient is φ = 863749264.

The previous prime is 864256663. The next prime is 864256703. The reversal of 864256681 is 186652468.

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

It can be written as a sum of positive squares in 2 ways, for example, as 141991056 + 722265625 = 11916^2 + 26875^2 .

It is a cyclic number.

It is not a de Polignac number, because 864256681 - 2¹⁹ = 863732393 is a prime.

It is a super-2 number, since 2×864256681² = 1493879221306271522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (864256181) by changing a digit.

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, 251146 + ... + 254563.

It is an arithmetic number, because the mean of its divisors is an integer number (216191025).

Almost surely, 2^864256681 is an apocalyptic number.

It is an amenable number.

864256681 is a deficient number, since it is larger than the sum of its proper divisors (507419).

864256681 is a wasteful number, since it uses less digits than its factorization.

864256681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507418.

The product of its digits is 552960, while the sum is 46.

The square root of 864256681 is about 29398.2428216382. The cubic root of 864256681 is about 952.5349402889.

The spelling of 864256681 in words is "eight hundred sixty-four million, two hundred fifty-six thousand, six hundred eighty-one".