565261 has 2 divisors, whose sum is σ = 565262. Its totient is φ = 565260.

The previous prime is 565259. The next prime is 565273. The reversal of 565261 is 162565.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 367236 + 198025 = 606^2 + 445^2 .

It is a cyclic number.

It is not a de Polignac number, because 565261 - 2¹ = 565259 is a prime.

Together with 565259, it forms a pair of twin primes.

565261 is a lucky number.

It is equal to p₄₆₄₆₅ and since 565261 and 46465 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (565241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 282630 + 282631.

It is an arithmetic number, because the mean of its divisors is an integer number (282631).

2⁵⁶⁵²⁶¹ is an apocalyptic number.

It is an amenable number.

565261 is a deficient number, since it is larger than the sum of its proper divisors (1).

565261 is an equidigital number, since it uses as much as digits as its factorization.

565261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1800, while the sum is 25.

The square root of 565261 is about 751.8384134906. The cubic root of 565261 is about 82.6830218969.

The spelling of 565261 in words is "five hundred sixty-five thousand, two hundred sixty-one".