256838 has 8 divisors (see below), whose sum is σ = 392688. Its totient is φ = 125944.

The previous prime is 256831. The next prime is 256873. The reversal of 256838 is 838652.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256831) by changing a digit.

256838 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1106 + ... + 1317.

It is an arithmetic number, because the mean of its divisors is an integer number (49086).

2²⁵⁶⁸³⁸ is an apocalyptic number.

256838 is a deficient number, since it is larger than the sum of its proper divisors (135850).

256838 is a wasteful number, since it uses less digits than its factorization.

256838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2478.

The product of its digits is 11520, while the sum is 32.

The square root of 256838 is about 506.7918704952. The cubic root of 256838 is about 63.5652500593.

The spelling of 256838 in words is "two hundred fifty-six thousand, eight hundred thirty-eight".