165803 has 4 divisors (see below), whose sum is σ = 180888. Its totient is φ = 150720.

The previous prime is 165799. The next prime is 165811. The reversal of 165803 is 308561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 308561 = 11 ⋅28051.

It is a cyclic number.

It is not a de Polignac number, because 165803 - 2² = 165799 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 165803.

It is not an unprimeable number, because it can be changed into a prime (165833) 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, 7526 + ... + 7547.

It is an arithmetic number, because the mean of its divisors is an integer number (45222).

2¹⁶⁵⁸⁰³ is an apocalyptic number.

165803 is a deficient number, since it is larger than the sum of its proper divisors (15085).

165803 is a wasteful number, since it uses less digits than its factorization.

165803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15084.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 165803 is about 407.1891452384. The cubic root of 165803 is about 54.9368973256.

The spelling of 165803 in words is "one hundred sixty-five thousand, eight hundred three".