256406263 has 4 divisors (see below), whose sum is σ = 263336200. Its totient is φ = 249476328.

The previous prime is 256406237. The next prime is 256406279. The reversal of 256406263 is 362604652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256406263 - 2²⁵ = 222851831 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256406663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3464913 + ... + 3464986.

It is an arithmetic number, because the mean of its divisors is an integer number (65834050).

Almost surely, 2^256406263 is an apocalyptic number.

256406263 is a deficient number, since it is larger than the sum of its proper divisors (6929937).

256406263 is an equidigital number, since it uses as much as digits as its factorization.

256406263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6929936.

The product of its (nonzero) digits is 51840, while the sum is 34.

The square root of 256406263 is about 16012.6906858279. The cubic root of 256406263 is about 635.2961298853.

The spelling of 256406263 in words is "two hundred fifty-six million, four hundred six thousand, two hundred sixty-three".