130561 has 4 divisors (see below), whose sum is σ = 131652. Its totient is φ = 129472.

The previous prime is 130553. The next prime is 130579. The reversal of 130561 is 165031.

130561 = 255² + 256².

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 165031 = 79 ⋅2089.

It can be written as a sum of positive squares in 2 ways, for example, as 65536 + 65025 = 256^2 + 255^2 .

It is a cyclic number.

It is not a de Polignac number, because 130561 - 2³ = 130553 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (130531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 340 + ... + 613.

It is an arithmetic number, because the mean of its divisors is an integer number (32913).

It is a Proth number, since it is equal to 255 ⋅ 2⁹ + 1 and 255 < 2⁹.

It is a Poulet number, since it divides 2¹³⁰⁵⁶⁰-1.

2¹³⁰⁵⁶¹ is an apocalyptic number.

130561 is the 256-th centered square number.

It is an amenable number.

130561 is a deficient number, since it is larger than the sum of its proper divisors (1091).

130561 is an equidigital number, since it uses as much as digits as its factorization.

130561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1090.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 130561 is about 361.3322570710. The cubic root of 130561 is about 50.7307351633.

Adding to 130561 its reverse (165031), we get a palindrome (295592).

The spelling of 130561 in words is "one hundred thirty thousand, five hundred sixty-one".