561321 has 12 divisors (see below), whose sum is σ = 828672. Its totient is φ = 365976.

The previous prime is 561313. The next prime is 561343. The reversal of 561321 is 123165.

It is not a de Polignac number, because 561321 - 2³ = 561313 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 561294 and 561303.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 561321.

It is not an unprimeable number, because it can be changed into a prime (561521) 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 in 11 ways as a sum of consecutive naturals, for example, 241 + ... + 1086.

It is an arithmetic number, because the mean of its divisors is an integer number (69056).

2⁵⁶¹³²¹ is an apocalyptic number.

It is an amenable number.

561321 is a deficient number, since it is larger than the sum of its proper divisors (267351).

561321 is a wasteful number, since it uses less digits than its factorization.

561321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1380 (or 1377 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 561321 is about 749.2135877038. The cubic root of 561321 is about 82.4904672181.

Adding to 561321 its reverse (123165), we get a palindrome (684486).

It can be divided in two parts, 561 and 321, that multiplied together give a palindrome (180081).

The spelling of 561321 in words is "five hundred sixty-one thousand, three hundred twenty-one".