565440989 has 2 divisors, whose sum is σ = 565440990. Its totient is φ = 565440988.

The previous prime is 565440979. The next prime is 565441027. The reversal of 565440989 is 989044565.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 382515364 + 182925625 = 19558^2 + 13525^2 .

It is a cyclic number.

It is not a de Polignac number, because 565440989 - 2¹⁶ = 565375453 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (565440929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 282720494 + 282720495.

It is an arithmetic number, because the mean of its divisors is an integer number (282720495).

Almost surely, 2^565440989 is an apocalyptic number.

It is an amenable number.

565440989 is a deficient number, since it is larger than the sum of its proper divisors (1).

565440989 is an equidigital number, since it uses as much as digits as its factorization.

565440989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1555200, while the sum is 50.

The square root of 565440989 is about 23779.0031119894. The cubic root of 565440989 is about 826.9179687295.

The spelling of 565440989 in words is "five hundred sixty-five million, four hundred forty thousand, nine hundred eighty-nine".