561761 has 2 divisors, whose sum is σ = 561762.
Its totient is φ = 561760.
The previous prime is 561733. The next prime is 561767. The reversal of 561761 is 167165.
561761 is nontrivially palindromic in base 5.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 547600 + 14161 = 740^2 + 119^2
It is a cyclic number.
It is not a de Polignac number, because 561761 - 210 = 560737 is a prime.
It is a super-2 number, since 2×5617612 = 631150842242, which contains 22 as substring.
It is a Chen prime.
It is a self number, because there is not a number n which added to its sum of digits gives 561761.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 561761.
It is not a weakly prime, because it can be changed into another prime (561767) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280880 + 280881.
It is an arithmetic number, because the mean of its divisors is an integer number (280881).
2561761 is an apocalyptic number.
It is an amenable number.
561761 is a deficient number, since it is larger than the sum of its proper divisors (1).
561761 is an equidigital number, since it uses as much as digits as its factorization.
561761 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 1260, while the sum is 26.
The square root of 561761 is about 749.5071714133.
The cubic root of 561761 is about 82.5120153911.
The spelling of 561761 in words is "five hundred sixty-one thousand, seven hundred sixty-one".