501565 has 4 divisors (see below), whose sum is σ = 601884. Its totient is φ = 401248.

The previous prime is 501563. The next prime is 501577. The reversal of 501565 is 565105.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 565105 = 5 ⋅113021.

It can be written as a sum of positive squares in 2 ways, for example, as 89401 + 412164 = 299^2 + 642^2 .

It is a cyclic number.

It is not a de Polignac number, because 501565 - 2¹ = 501563 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50152 + ... + 50161.

It is an arithmetic number, because the mean of its divisors is an integer number (150471).

2⁵⁰¹⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

501565 is a deficient number, since it is larger than the sum of its proper divisors (100319).

501565 is a wasteful number, since it uses less digits than its factorization.

501565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100318.

The product of its (nonzero) digits is 750, while the sum is 22.

The square root of 501565 is about 708.2125387198. The cubic root of 501565 is about 79.4527757720.

The spelling of 501565 in words is "five hundred one thousand, five hundred sixty-five".