256228565 has 4 divisors (see below), whose sum is σ = 307474284. Its totient is φ = 204982848.

The previous prime is 256228541. The next prime is 256228571. The reversal of 256228565 is 565822652.

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

It can be written as a sum of positive squares in 2 ways, for example, as 184470724 + 71757841 = 13582^2 + 8471^2 .

It is a cyclic number.

It is not a de Polignac number, because 256228565 - 2⁶ = 256228501 is a prime.

It is a Duffinian number.

It is a congruent 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, 25622852 + ... + 25622861.

It is an arithmetic number, because the mean of its divisors is an integer number (76868571).

Almost surely, 2^256228565 is an apocalyptic number.

It is an amenable number.

256228565 is a deficient number, since it is larger than the sum of its proper divisors (51245719).

256228565 is an equidigital number, since it uses as much as digits as its factorization.

256228565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51245718.

The product of its digits is 288000, while the sum is 41.

The square root of 256228565 is about 16007.1410626633. The cubic root of 256228565 is about 635.1493355761.

The spelling of 256228565 in words is "two hundred fifty-six million, two hundred twenty-eight thousand, five hundred sixty-five".