655989 has 8 divisors (see below), whose sum is σ = 878400. Its totient is φ = 435456.

The previous prime is 655987. The next prime is 656023. The reversal of 655989 is 989556.

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

It is not a de Polignac number, because 655989 - 2¹ = 655987 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 655989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1104 + ... + 1590.

It is an arithmetic number, because the mean of its divisors is an integer number (109800).

2⁶⁵⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

655989 is a deficient number, since it is larger than the sum of its proper divisors (222411).

655989 is a wasteful number, since it uses less digits than its factorization.

655989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 939.

The product of its digits is 97200, while the sum is 42.

The square root of 655989 is about 809.9314785832. The cubic root of 655989 is about 86.8891440491.

The spelling of 655989 in words is "six hundred fifty-five thousand, nine hundred eighty-nine".