256288091 has 2 divisors, whose sum is σ = 256288092. Its totient is φ = 256288090.

The previous prime is 256288079. The next prime is 256288111. The reversal of 256288091 is 190882652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256288091 - 2¹⁴ = 256271707 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (256288031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128144045 + 128144046.

It is an arithmetic number, because the mean of its divisors is an integer number (128144046).

Almost surely, 2^256288091 is an apocalyptic number.

256288091 is a deficient number, since it is larger than the sum of its proper divisors (1).

256288091 is an equidigital number, since it uses as much as digits as its factorization.

256288091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 256288091 is about 16009.0003123243. Note that the first 3 decimals coincide. The cubic root of 256288091 is about 635.1985168893.

The spelling of 256288091 in words is "two hundred fifty-six million, two hundred eighty-eight thousand, ninety-one".