561666041 has 2 divisors, whose sum is σ = 561666042. Its totient is φ = 561666040.

The previous prime is 561666023. The next prime is 561666067. The reversal of 561666041 is 140666165.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 548496400 + 13169641 = 23420^2 + 3629^2 .

It is a cyclic number.

It is not a de Polignac number, because 561666041 - 2⁶ = 561665977 is a prime.

It is a super-2 number, since 2×561666041² = 630937483225227362, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 561665992 and 561666010.

It is not a weakly prime, because it can be changed into another prime (561666071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280833020 + 280833021.

It is an arithmetic number, because the mean of its divisors is an integer number (280833021).

Almost surely, 2^561666041 is an apocalyptic number.

It is an amenable number.

561666041 is a deficient number, since it is larger than the sum of its proper divisors (1).

561666041 is an equidigital number, since it uses as much as digits as its factorization.

561666041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 561666041 is about 23699.4945304747. The cubic root of 561666041 is about 825.0736590492.

The spelling of 561666041 in words is "five hundred sixty-one million, six hundred sixty-six thousand, forty-one".