256623 has 8 divisors (see below), whose sum is σ = 345648. Its totient is φ = 169344.

The previous prime is 256609. The next prime is 256639. The reversal of 256623 is 326652.

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

It is not a de Polignac number, because 256623 - 2¹³ = 248431 is a prime.

256623 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 256593 and 256602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256603) 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 7 ways as a sum of consecutive naturals, for example, 40 + ... + 717.

It is an arithmetic number, because the mean of its divisors is an integer number (43206).

2²⁵⁶⁶²³ is an apocalyptic number.

256623 is a deficient number, since it is larger than the sum of its proper divisors (89025).

256623 is a wasteful number, since it uses less digits than its factorization.

256623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873.

The product of its digits is 2160, while the sum is 24.

The square root of 256623 is about 506.5797074499. The cubic root of 256623 is about 63.5475082091.

The spelling of 256623 in words is "two hundred fifty-six thousand, six hundred twenty-three".