655809 has 32 divisors (see below), whose sum is σ = 1161216. Its totient is φ = 318720.

The previous prime is 655807. The next prime is 655847. The reversal of 655809 is 908556.

655809 = T₆₂ + T₆₃ + ... + T₁₆₀.

It is not a de Polignac number, because 655809 - 2¹ = 655807 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

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 655809.

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 655809.

It is not an unprimeable number, because it can be changed into a prime (655807) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3844 + ... + 4010.

It is an arithmetic number, because the mean of its divisors is an integer number (36288).

2⁶⁵⁵⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

655809 is a deficient number, since it is larger than the sum of its proper divisors (505407).

655809 is a wasteful number, since it uses less digits than its factorization.

655809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205.

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 655809 is about 809.8203504482. The cubic root of 655809 is about 86.8811960110.

The spelling of 655809 in words is "six hundred fifty-five thousand, eight hundred nine".