4020565 has 4 divisors (see below), whose sum is σ = 4824684. Its totient is φ = 3216448.

The previous prime is 4020563. The next prime is 4020587. The reversal of 4020565 is 5650204.

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 1779556 + 2241009 = 1334^2 + 1497^2 .

It is a cyclic number.

It is not a de Polignac number, because 4020565 - 2¹ = 4020563 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4020563) 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, 402052 + ... + 402061.

It is an arithmetic number, because the mean of its divisors is an integer number (1206171).

Almost surely, 2^4020565 is an apocalyptic number.

It is an amenable number.

4020565 is a deficient number, since it is larger than the sum of its proper divisors (804119).

4020565 is an equidigital number, since it uses as much as digits as its factorization.

4020565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 804118.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 4020565 is about 2005.1346588197. The cubic root of 4020565 is about 159.0116811692.

Adding to 4020565 its reverse (5650204), we get a palindrome (9670769).

The spelling of 4020565 in words is "four million, twenty thousand, five hundred sixty-five".