256611571 has 8 divisors (see below), whose sum is σ = 260635104. Its totient is φ = 252601920.

The previous prime is 256611569. The next prime is 256611599. The reversal of 256611571 is 175116652.

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

It is a cyclic number.

It is not a de Polignac number, because 256611571 - 2¹ = 256611569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256611871) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 37506 + ... + 43816.

It is an arithmetic number, because the mean of its divisors is an integer number (32579388).

Almost surely, 2^256611571 is an apocalyptic number.

256611571 is a deficient number, since it is larger than the sum of its proper divisors (4023533).

256611571 is an equidigital number, since it uses as much as digits as its factorization.

256611571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6941.

The product of its digits is 12600, while the sum is 34.

The square root of 256611571 is about 16019.1001932069. The cubic root of 256611571 is about 635.4656480802.

The spelling of 256611571 in words is "two hundred fifty-six million, six hundred eleven thousand, five hundred seventy-one".