255581 has 4 divisors (see below), whose sum is σ = 257664. Its totient is φ = 253500.

The previous prime is 255571. The next prime is 255587. The reversal of 255581 is 185552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 255581 - 2⁶ = 255517 is a prime.

It is a super-2 number, since 2×255581² = 130643295122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 255581.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 255581.

It is not an unprimeable number, because it can be changed into a prime (255587) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 845 + ... + 1106.

It is an arithmetic number, because the mean of its divisors is an integer number (64416).

2²⁵⁵⁵⁸¹ is an apocalyptic number.

It is an amenable number.

255581 is a deficient number, since it is larger than the sum of its proper divisors (2083).

255581 is a wasteful number, since it uses less digits than its factorization.

255581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2082.

The product of its digits is 2000, while the sum is 26.

The square root of 255581 is about 505.5501953318. The cubic root of 255581 is about 63.4613814411.

The spelling of 255581 in words is "two hundred fifty-five thousand, five hundred eighty-one".