256561233 has 8 divisors (see below), whose sum is σ = 342223200. Its totient is φ = 170970048.

The previous prime is 256561183. The next prime is 256561241. The reversal of 256561233 is 332165652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 256561233 - 2⁸ = 256560977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 256561194 and 256561203.

It is not an unprimeable number, because it can be changed into a prime (256561243) 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 7 ways as a sum of consecutive naturals, for example, 8563 + ... + 24216.

It is an arithmetic number, because the mean of its divisors is an integer number (42777900).

Almost surely, 2^256561233 is an apocalyptic number.

It is an amenable number.

256561233 is a deficient number, since it is larger than the sum of its proper divisors (85661967).

256561233 is a wasteful number, since it uses less digits than its factorization.

256561233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35391.

The product of its digits is 32400, while the sum is 33.

The square root of 256561233 is about 16017.5289292700. The cubic root of 256561233 is about 635.4240934957.

The spelling of 256561233 in words is "two hundred fifty-six million, five hundred sixty-one thousand, two hundred thirty-three".