6450221 has 2 divisors, whose sum is σ = 6450222. Its totient is φ = 6450220.

The previous prime is 6450217. The next prime is 6450229. The reversal of 6450221 is 1220546.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5152900 + 1297321 = 2270^2 + 1139^2 .

It is a cyclic number.

It is not a de Polignac number, because 6450221 - 2² = 6450217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6450193 and 6450202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6450229) 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, 3225110 + 3225111.

It is an arithmetic number, because the mean of its divisors is an integer number (3225111).

Almost surely, 2^6450221 is an apocalyptic number.

It is an amenable number.

6450221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6450221 is an equidigital number, since it uses as much as digits as its factorization.

6450221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 6450221 is about 2539.7285287999. The cubic root of 6450221 is about 186.1479244884.

Adding to 6450221 its reverse (1220546), we get a palindrome (7670767).

The spelling of 6450221 in words is "six million, four hundred fifty thousand, two hundred twenty-one".