201865 has 8 divisors (see below), whose sum is σ = 247680. Its totient is φ = 157872.

The previous prime is 201847. The next prime is 201881. The reversal of 201865 is 568102.

It is a happy number.

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 201865 - 2⁵ = 201833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195 + ... + 664.

It is an arithmetic number, because the mean of its divisors is an integer number (30960).

2²⁰¹⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

201865 is a deficient number, since it is larger than the sum of its proper divisors (45815).

201865 is an equidigital number, since it uses as much as digits as its factorization.

201865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 201865 is about 449.2938904548. The cubic root of 201865 is about 58.6615690876.

Adding to 201865 its reverse (568102), we get a palindrome (769967).

The spelling of 201865 in words is "two hundred one thousand, eight hundred sixty-five".