56561321 has 2 divisors, whose sum is σ = 56561322. Its totient is φ = 56561320.

The previous prime is 56561287. The next prime is 56561341. The reversal of 56561321 is 12316565.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54922921 + 1638400 = 7411^2 + 1280^2 .

It is a cyclic number.

It is not a de Polignac number, because 56561321 - 2¹⁰ = 56560297 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (56561341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28280660 + 28280661.

It is an arithmetic number, because the mean of its divisors is an integer number (28280661).

Almost surely, 2^56561321 is an apocalyptic number.

It is an amenable number.

56561321 is a deficient number, since it is larger than the sum of its proper divisors (1).

56561321 is an equidigital number, since it uses as much as digits as its factorization.

56561321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5400, while the sum is 29.

The square root of 56561321 is about 7520.7260952650. The cubic root of 56561321 is about 383.8602849106.

Adding to 56561321 its reverse (12316565), we get a palindrome (68877886).

The spelling of 56561321 in words is "fifty-six million, five hundred sixty-one thousand, three hundred twenty-one".