It is a happy number.
It is an alternating number because its digits alternate between odd and even.
It is a congruent number.
123256 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
2123256 is an apocalyptic number.
123256 is the 496-th triangular number.
123256 is the 166-th centered nonagonal number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 123256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138240).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
123256 is a wasteful number, since it uses less digits than its factorization.
123256 is an odious number, because the sum of its binary digits is odd.
The square root of 123256 is about 351.0783388362. The cubic root of 123256 is about 49.7663767705.
Adding to 123256 its reverse (652321), we get a palindrome (775577).
The spelling of 123256 in words is "one hundred twenty-three thousand, two hundred fifty-six".