646589 has 4 divisors (see below), whose sum is σ = 680640. Its totient is φ = 612540.

The previous prime is 646577. The next prime is 646609. The reversal of 646589 is 985646.

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 646589 - 2⁴ = 646573 is a prime.

It is a Duffinian number.

It is a Curzon number.

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 646589.

It is not an unprimeable number, because it can be changed into a prime (646519) 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, 16997 + ... + 17034.

It is an arithmetic number, because the mean of its divisors is an integer number (170160).

2⁶⁴⁶⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

646589 is a deficient number, since it is larger than the sum of its proper divisors (34051).

646589 is a wasteful number, since it uses less digits than its factorization.

646589 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34050.

The product of its digits is 51840, while the sum is 38.

The square root of 646589 is about 804.1075798673. The cubic root of 646589 is about 86.4721194964.

The spelling of 646589 in words is "six hundred forty-six thousand, five hundred eighty-nine".