659985 has 16 divisors (see below), whose sum is σ = 1102464. Its totient is φ = 336512.

The previous prime is 659983. The next prime is 659999. The reversal of 659985 is 589956.

It is a cyclic number.

It is not a de Polignac number, because 659985 - 2¹ = 659983 is a prime.

Its product of digits (97200) is a multiple of the sum of its prime divisors (1944).

It is not an unprimeable number, because it can be changed into a prime (659983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 612 + ... + 1301.

It is an arithmetic number, because the mean of its divisors is an integer number (68904).

2⁶⁵⁹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

659985 is a deficient number, since it is larger than the sum of its proper divisors (442479).

659985 is a wasteful number, since it uses less digits than its factorization.

659985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1944.

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

The square root of 659985 is about 812.3946085493. The cubic root of 659985 is about 87.0652173168.

The spelling of 659985 in words is "six hundred fifty-nine thousand, nine hundred eighty-five".