557321 has 2 divisors, whose sum is σ = 557322. Its totient is φ = 557320.

The previous prime is 557309. The next prime is 557329. The reversal of 557321 is 123755.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 541696 + 15625 = 736^2 + 125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-557321 is a prime.

It is a plaindrome in base 13.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 557321.

It is not a weakly prime, because it can be changed into another prime (557329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 278660 + 278661.

It is an arithmetic number, because the mean of its divisors is an integer number (278661).

2⁵⁵⁷³²¹ is an apocalyptic number.

It is an amenable number.

557321 is a deficient number, since it is larger than the sum of its proper divisors (1).

557321 is an equidigital number, since it uses as much as digits as its factorization.

557321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1050, while the sum is 23.

The square root of 557321 is about 746.5393492643. The cubic root of 557321 is about 82.2940562749.

It can be divided in two parts, 557 and 321, that added together give a palindrome (878).

The spelling of 557321 in words is "five hundred fifty-seven thousand, three hundred twenty-one".