201689 has 4 divisors (see below), whose sum is σ = 203280. Its totient is φ = 200100.

The previous prime is 201683. The next prime is 201701. The reversal of 201689 is 986102.

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 201689 - 2⁴ = 201673 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (201683) 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, 587 + ... + 864.

It is an arithmetic number, because the mean of its divisors is an integer number (50820).

2²⁰¹⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

201689 is a deficient number, since it is larger than the sum of its proper divisors (1591).

201689 is a wasteful number, since it uses less digits than its factorization.

201689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1590.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 201689 is about 449.0979848541. The cubic root of 201689 is about 58.6445157134.

The spelling of 201689 in words is "two hundred one thousand, six hundred eighty-nine".