6521321 has 2 divisors, whose sum is σ = 6521322. Its totient is φ = 6521320.

The previous prime is 6521303. The next prime is 6521363. The reversal of 6521321 is 1231256.

6521321 is digitally balanced in base 3, 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., 5107600 + 1413721 = 2260^2 + 1189^2 .

It is a cyclic number.

It is not a de Polignac number, because 6521321 - 2⁶ = 6521257 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 6521293 and 6521302.

It is not a weakly prime, because it can be changed into another prime (6521381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3260660 + 3260661.

It is an arithmetic number, because the mean of its divisors is an integer number (3260661).

Almost surely, 2^6521321 is an apocalyptic number.

It is an amenable number.

6521321 is a deficient number, since it is larger than the sum of its proper divisors (1).

6521321 is an equidigital number, since it uses as much as digits as its factorization.

6521321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 360, while the sum is 20.

The square root of 6521321 is about 2553.6877256235. The cubic root of 6521321 is about 186.8293886514.

Adding to 6521321 its reverse (1231256), we get a palindrome (7752577).

The spelling of 6521321 in words is "six million, five hundred twenty-one thousand, three hundred twenty-one".