256971 has 16 divisors (see below), whose sum is σ = 403200. Its totient is φ = 143520.

The previous prime is 256967. The next prime is 256981. The reversal of 256971 is 179652.

It is not a de Polignac number, because 256971 - 2² = 256967 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 130 + ... + 728.

It is an arithmetic number, because the mean of its divisors is an integer number (25200).

2²⁵⁶⁹⁷¹ is an apocalyptic number.

256971 is a deficient number, since it is larger than the sum of its proper divisors (146229).

256971 is a wasteful number, since it uses less digits than its factorization.

256971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626.

The product of its digits is 3780, while the sum is 30.

The square root of 256971 is about 506.9230710867. The cubic root of 256971 is about 63.5762202940.

It can be divided in two parts, 25 and 6971, that added together give a palindrome (6996).

The spelling of 256971 in words is "two hundred fifty-six thousand, nine hundred seventy-one".