256171231 has 8 divisors (see below), whose sum is σ = 258740064. Its totient is φ = 253612800.

The previous prime is 256171219. The next prime is 256171241. The reversal of 256171231 is 132171652.

It is a happy number.

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 256171231 - 2⁵ = 256171199 is a prime.

It is a super-2 number, since 2×256171231² = 131247399184110722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256171231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256171241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52606 + ... + 57268.

It is an arithmetic number, because the mean of its divisors is an integer number (32342508).

Almost surely, 2^256171231 is an apocalyptic number.

256171231 is a deficient number, since it is larger than the sum of its proper divisors (2568833).

256171231 is a wasteful number, since it uses less digits than its factorization.

256171231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5201.

The product of its digits is 2520, while the sum is 28.

The square root of 256171231 is about 16005.3500742720. The cubic root of 256171231 is about 635.1019581256.

The spelling of 256171231 in words is "two hundred fifty-six million, one hundred seventy-one thousand, two hundred thirty-one".