659921 has 8 divisors (see below), whose sum is σ = 686400. Its totient is φ = 634032.

The previous prime is 659917. The next prime is 659941. The reversal of 659921 is 129956.

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

It is a cyclic number.

It is not a de Polignac number, because 659921 - 2² = 659917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (659941) 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, 4355 + ... + 4503.

It is an arithmetic number, because the mean of its divisors is an integer number (85800).

2⁶⁵⁹⁹²¹ is an apocalyptic number.

It is an amenable number.

659921 is a deficient number, since it is larger than the sum of its proper divisors (26479).

659921 is a wasteful number, since it uses less digits than its factorization.

659921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295.

The product of its digits is 4860, while the sum is 32.

The square root of 659921 is about 812.3552178696. The cubic root of 659921 is about 87.0624029326.

The spelling of 659921 in words is "six hundred fifty-nine thousand, nine hundred twenty-one".