6444333221 has 2 divisors, whose sum is σ = 6444333222. Its totient is φ = 6444333220.

The previous prime is 6444333211. The next prime is 6444333241. The reversal of 6444333221 is 1223334446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3538584196 + 2905749025 = 59486^2 + 53905^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6444333221 is a prime.

It is a super-4 number, since 4×6444333221⁴ (a number of 40 digits) contains 4444 as substring.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6444333211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3222166610 + 3222166611.

It is an arithmetic number, because the mean of its divisors is an integer number (3222166611).

Almost surely, 2^6444333221 is an apocalyptic number.

It is an amenable number.

6444333221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6444333221 is an equidigital number, since it uses as much as digits as its factorization.

6444333221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 32.

The square root of 6444333221 is about 80276.6044436360. The cubic root of 6444333221 is about 1860.9126847166.

Adding to 6444333221 its reverse (1223334446), we get a palindrome (7667667667).

The spelling of 6444333221 in words is "six billion, four hundred forty-four million, three hundred thirty-three thousand, two hundred twenty-one".