256000289 has 4 divisors (see below), whose sum is σ = 256645524. Its totient is φ = 255355056.

The previous prime is 256000279. The next prime is 256000307. The reversal of 256000289 is 982000652.

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 171819664 + 84180625 = 13108^2 + 9175^2 .

It is a cyclic number.

It is not a de Polignac number, because 256000289 - 2⁸ = 256000033 is a prime.

It is a super-2 number, since 2×256000289² = 131072295936167042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256000219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 322022 + ... + 322815.

It is an arithmetic number, because the mean of its divisors is an integer number (64161381).

Almost surely, 2^256000289 is an apocalyptic number.

It is an amenable number.

256000289 is a deficient number, since it is larger than the sum of its proper divisors (645235).

256000289 is an equidigital number, since it uses as much as digits as its factorization.

256000289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645234.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 256000289 is about 16000.0090312475. The cubic root of 256000289 is about 634.9606597241.

The spelling of 256000289 in words is "two hundred fifty-six million, two hundred eighty-nine", and thus it is an aban number.