256505258 has 8 divisors (see below), whose sum is σ = 389628480. Its totient is φ = 126629100.

The previous prime is 256505173. The next prime is 256505267. The reversal of 256505258 is 852505652.

It is a happy number.

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

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is an unprimeable number.

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, 811568 + ... + 811883.

It is an arithmetic number, because the mean of its divisors is an integer number (48703560).

Almost surely, 2^256505258 is an apocalyptic number.

256505258 is a deficient number, since it is larger than the sum of its proper divisors (133123222).

256505258 is a wasteful number, since it uses less digits than its factorization.

256505258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623532.

The product of its (nonzero) digits is 120000, while the sum is 38.

The square root of 256505258 is about 16015.7815294790. The cubic root of 256505258 is about 635.3778791213.

The spelling of 256505258 in words is "two hundred fifty-six million, five hundred five thousand, two hundred fifty-eight".