245569 has 4 divisors (see below), whose sum is σ = 252244. Its totient is φ = 238896.

The previous prime is 245563. The next prime is 245587. The reversal of 245569 is 965542.

245569 = 17² + 18² + ... + 90².

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 97344 + 148225 = 312^2 + 385^2 .

It is a cyclic number.

It is not a de Polignac number, because 245569 - 2³ = 245561 is a prime.

It is a super-2 number, since 2×245569² = 120608267522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 245569.

It is not an unprimeable number, because it can be changed into a prime (245561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3282 + ... + 3355.

It is an arithmetic number, because the mean of its divisors is an integer number (63061).

2²⁴⁵⁵⁶⁹ is an apocalyptic number.

It is an amenable number.

245569 is a deficient number, since it is larger than the sum of its proper divisors (6675).

245569 is an equidigital number, since it uses as much as digits as its factorization.

245569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6674.

The product of its digits is 10800, while the sum is 31.

The square root of 245569 is about 495.5491902930. The cubic root of 245569 is about 62.6216510627.

The spelling of 245569 in words is "two hundred forty-five thousand, five hundred sixty-nine".