20041565 has 4 divisors (see below), whose sum is σ = 24049884. Its totient is φ = 16033248.

The previous prime is 20041537. The next prime is 20041573. The reversal of 20041565 is 56514002.

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 13980121 + 6061444 = 3739^2 + 2462^2 .

It is a cyclic number.

It is not a de Polignac number, because 20041565 - 2⁶ = 20041501 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20041565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2004152 + ... + 2004161.

It is an arithmetic number, because the mean of its divisors is an integer number (6012471).

Almost surely, 2^20041565 is an apocalyptic number.

It is an amenable number.

20041565 is a deficient number, since it is larger than the sum of its proper divisors (4008319).

20041565 is an equidigital number, since it uses as much as digits as its factorization.

20041565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4008318.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 20041565 is about 4476.7806513163. The cubic root of 20041565 is about 271.6296728245.

Adding to 20041565 its reverse (56514002), we get a palindrome (76555567).

It can be divided in two parts, 2004 and 1565, that multiplied together give a triangular number (3136260 = T₂₅₀₄).

The spelling of 20041565 in words is "twenty million, forty-one thousand, five hundred sixty-five".