256564265 has 8 divisors (see below), whose sum is σ = 315386568. Its totient is φ = 200245120.

The previous prime is 256564249. The next prime is 256564307. The reversal of 256564265 is 562465652.

It can be written as a sum of positive squares in 4 ways, for example, as 34762816 + 221801449 = 5896^2 + 14893^2 .

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

It is not a de Polignac number, because 256564265 - 2⁴ = 256564249 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 625562 + ... + 625971.

It is an arithmetic number, because the mean of its divisors is an integer number (39423321).

Almost surely, 2^256564265 is an apocalyptic number.

It is an amenable number.

256564265 is a deficient number, since it is larger than the sum of its proper divisors (58822303).

256564265 is a wasteful number, since it uses less digits than its factorization.

256564265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1251579.

The product of its digits is 432000, while the sum is 41.

The square root of 256564265 is about 16017.6235752998. The cubic root of 256564265 is about 635.4265965996.

The spelling of 256564265 in words is "two hundred fifty-six million, five hundred sixty-four thousand, two hundred sixty-five".