573561 has 20 divisors (see below), whose sum is σ = 877492. Its totient is φ = 373248.

The previous prime is 573557. The next prime is 573569. The reversal of 573561 is 165375.

It can be written as a sum of positive squares in 2 ways, for example, as 291600 + 281961 = 540^2 + 531^2 .

It is not a de Polignac number, because 573561 - 2² = 573557 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

573561 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (573569) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 5865 + ... + 5961.

2⁵⁷³⁵⁶¹ is an apocalyptic number.

It is an amenable number.

573561 is a deficient number, since it is larger than the sum of its proper divisors (303931).

573561 is an equidigital number, since it uses as much as digits as its factorization.

573561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 173 counting only the distinct ones).

The product of its digits is 3150, while the sum is 27.

The square root of 573561 is about 757.3381015108. The cubic root of 573561 is about 83.0857487063.

The spelling of 573561 in words is "five hundred seventy-three thousand, five hundred sixty-one".