256123 has 6 divisors (see below), whose sum is σ = 297996. Its totient is φ = 219492.

The previous prime is 256121. The next prime is 256129. The reversal of 256123 is 321652.

It is a happy number.

It is not a de Polignac number, because 256123 - 2¹ = 256121 is a prime.

It is a super-2 number, since 2×256123² = 131197982258, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

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 256123.

It is not an unprimeable number, because it can be changed into a prime (256121) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2565 + ... + 2662.

It is an arithmetic number, because the mean of its divisors is an integer number (49666).

2²⁵⁶¹²³ is an apocalyptic number.

256123 is a deficient number, since it is larger than the sum of its proper divisors (41873).

256123 is an equidigital number, since it uses as much as digits as its factorization.

256123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5241 (or 5234 counting only the distinct ones).

The product of its digits is 360, while the sum is 19.

The square root of 256123 is about 506.0859610778. The cubic root of 256123 is about 63.5062097385.

Adding to 256123 its reverse (321652), we get a palindrome (577775).

The spelling of 256123 in words is "two hundred fifty-six thousand, one hundred twenty-three".