256850681 has 2 divisors, whose sum is σ = 256850682. Its totient is φ = 256850680.

The previous prime is 256850677. The next prime is 256850689. The reversal of 256850681 is 186058652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 240529081 + 16321600 = 15509^2 + 4040^2 .

It is a cyclic number.

It is not a de Polignac number, because 256850681 - 2² = 256850677 is a prime.

It is a super-2 number, since 2×256850681² = 131944544660327522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (256850689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128425340 + 128425341.

It is an arithmetic number, because the mean of its divisors is an integer number (128425341).

Almost surely, 2^256850681 is an apocalyptic number.

It is an amenable number.

256850681 is a deficient number, since it is larger than the sum of its proper divisors (1).

256850681 is an equidigital number, since it uses as much as digits as its factorization.

256850681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115200, while the sum is 41.

The square root of 256850681 is about 16026.5617335722. The cubic root of 256850681 is about 635.6629618914.

The spelling of 256850681 in words is "two hundred fifty-six million, eight hundred fifty thousand, six hundred eighty-one".