256563293 has 4 divisors (see below), whose sum is σ = 293215200. Its totient is φ = 219911388.

The previous prime is 256563259. The next prime is 256563311. The reversal of 256563293 is 392365652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256563293 - 2¹⁰ = 256562269 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 256563293.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256563253) 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, 18325943 + ... + 18325956.

It is an arithmetic number, because the mean of its divisors is an integer number (73303800).

Almost surely, 2^256563293 is an apocalyptic number.

It is an amenable number.

256563293 is a deficient number, since it is larger than the sum of its proper divisors (36651907).

256563293 is an equidigital number, since it uses as much as digits as its factorization.

256563293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36651906.

The product of its digits is 291600, while the sum is 41.

The square root of 256563293 is about 16017.5932336915. The cubic root of 256563293 is about 635.4257941555.

The spelling of 256563293 in words is "two hundred fifty-six million, five hundred sixty-three thousand, two hundred ninety-three".