256424491 has 4 divisors (see below), whose sum is σ = 256477000. Its totient is φ = 256371984.

The previous prime is 256424479. The next prime is 256424501. The reversal of 256424491 is 194424652.

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 256424491 - 2²³ = 248035883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256424491.

It is not an unprimeable number, because it can be changed into a prime (256424431) 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, 18081 + ... + 28978.

It is an arithmetic number, because the mean of its divisors is an integer number (64119250).

Almost surely, 2^256424491 is an apocalyptic number.

256424491 is a deficient number, since it is larger than the sum of its proper divisors (52509).

256424491 is an equidigital number, since it uses as much as digits as its factorization.

256424491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52508.

The product of its digits is 69120, while the sum is 37.

The square root of 256424491 is about 16013.2598492624. The cubic root of 256424491 is about 635.3111839943.

The spelling of 256424491 in words is "two hundred fifty-six million, four hundred twenty-four thousand, four hundred ninety-one".