505989 has 24 divisors (see below), whose sum is σ = 842400. Its totient is φ = 289440.

The previous prime is 505979. The next prime is 506047. The reversal of 505989 is 989505.

It is a de Polignac number, because none of the positive numbers 2^k-505989 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505919) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1747 + ... + 2015.

It is an arithmetic number, because the mean of its divisors is an integer number (35100).

2⁵⁰⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

505989 is a deficient number, since it is larger than the sum of its proper divisors (336411).

505989 is a wasteful number, since it uses less digits than its factorization.

505989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305 (or 302 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 36.

The square root of 505989 is about 711.3290377877. The cubic root of 505989 is about 79.6856938460.

The spelling of 505989 in words is "five hundred five thousand, nine hundred eighty-nine".