801565 has 4 divisors (see below), whose sum is σ = 961884. Its totient is φ = 641248.

The previous prime is 801557. The next prime is 801569. The reversal of 801565 is 565108.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 550564 + 251001 = 742^2 + 501^2 .

It is a cyclic number.

It is not a de Polignac number, because 801565 - 2³ = 801557 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 (801569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 80152 + ... + 80161.

It is an arithmetic number, because the mean of its divisors is an integer number (240471).

2⁸⁰¹⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

801565 is a deficient number, since it is larger than the sum of its proper divisors (160319).

801565 is a wasteful number, since it uses less digits than its factorization.

801565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160318.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 801565 is about 895.3016251521. The cubic root of 801565 is about 92.8922712962.

The spelling of 801565 in words is "eight hundred one thousand, five hundred sixty-five".