256859761 has 4 divisors (see below), whose sum is σ = 257814900. Its totient is φ = 255904624.

The previous prime is 256859741. The next prime is 256859777. The reversal of 256859761 is 167958652.

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 55219761 + 201640000 = 7431^2 + 14200^2 .

It is a cyclic number.

It is not a de Polignac number, because 256859761 - 2⁷ = 256859633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256859741) 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, 477166 + ... + 477703.

It is an arithmetic number, because the mean of its divisors is an integer number (64453725).

Almost surely, 2^256859761 is an apocalyptic number.

It is an amenable number.

256859761 is a deficient number, since it is larger than the sum of its proper divisors (955139).

256859761 is an equidigital number, since it uses as much as digits as its factorization.

256859761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 955138.

The product of its digits is 907200, while the sum is 49.

The square root of 256859761 is about 16026.8450107936. The cubic root of 256859761 is about 635.6704523026.

The spelling of 256859761 in words is "two hundred fifty-six million, eight hundred fifty-nine thousand, seven hundred sixty-one".