561500549 has 2 divisors, whose sum is σ = 561500550. Its totient is φ = 561500548.

The previous prime is 561500543. The next prime is 561500557. The reversal of 561500549 is 945005165.

561500549 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 561453025 + 47524 = 23695^2 + 218^2 .

It is a cyclic number.

It is not a de Polignac number, because 561500549 - 2²⁸ = 293065093 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561500543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280750274 + 280750275.

It is an arithmetic number, because the mean of its divisors is an integer number (280750275).

Almost surely, 2^561500549 is an apocalyptic number.

It is an amenable number.

561500549 is a deficient number, since it is larger than the sum of its proper divisors (1).

561500549 is an equidigital number, since it uses as much as digits as its factorization.

561500549 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 35.

The square root of 561500549 is about 23696.0028063807. The cubic root of 561500549 is about 824.9926165241.

The spelling of 561500549 in words is "five hundred sixty-one million, five hundred thousand, five hundred forty-nine".