402565 has 4 divisors (see below), whose sum is σ = 483084. Its totient is φ = 322048.

The previous prime is 402559. The next prime is 402581. The reversal of 402565 is 565204.

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 49729 + 352836 = 223^2 + 594^2 .

It is a cyclic number.

It is not a de Polignac number, because 402565 - 2⁹ = 402053 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 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 3 ways as a sum of consecutive naturals, for example, 40252 + ... + 40261.

It is an arithmetic number, because the mean of its divisors is an integer number (120771).

2⁴⁰²⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

402565 is a deficient number, since it is larger than the sum of its proper divisors (80519).

402565 is an equidigital number, since it uses as much as digits as its factorization.

402565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80518.

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

The square root of 402565 is about 634.4801021309. The cubic root of 402565 is about 73.8377868737.

Adding to 402565 its reverse (565204), we get a palindrome (967769).

The spelling of 402565 in words is "four hundred two thousand, five hundred sixty-five".