20340565 has 32 divisors (see below), whose sum is σ = 29111040. Its totient is φ = 13353984.

The previous prime is 20340563. The next prime is 20340569. The reversal of 20340565 is 56504302.

20340565 = T₄₇₀ + T₄₇₁ + ... + T₆₀₈.

It is not a de Polignac number, because 20340565 - 2¹ = 20340563 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20340563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 146266 + ... + 146404.

It is an arithmetic number, because the mean of its divisors is an integer number (909720).

Almost surely, 2^20340565 is an apocalyptic number.

It is an amenable number.

20340565 is a deficient number, since it is larger than the sum of its proper divisors (8770475).

20340565 is a wasteful number, since it uses less digits than its factorization.

20340565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301.

The product of its (nonzero) digits is 3600, while the sum is 25.

The square root of 20340565 is about 4510.0515518118. The cubic root of 20340565 is about 272.9738242334.

Adding to 20340565 its reverse (56504302), we get a palindrome (76844867).

It can be divided in two parts, 20340 and 565, that multiplied together give a square (11492100 = 3390²).

The spelling of 20340565 in words is "twenty million, three hundred forty thousand, five hundred sixty-five".