6405000221 has 2 divisors, whose sum is σ = 6405000222. Its totient is φ = 6405000220.

The previous prime is 6405000211. The next prime is 6405000229. The reversal of 6405000221 is 1220005046.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3904500196 + 2500500025 = 62486^2 + 50005^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6405000221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6405000193 and 6405000202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6405000229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3202500110 + 3202500111.

It is an arithmetic number, because the mean of its divisors is an integer number (3202500111).

Almost surely, 2^6405000221 is an apocalyptic number.

It is an amenable number.

6405000221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6405000221 is an equidigital number, since it uses as much as digits as its factorization.

6405000221 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 6405000221 is about 80031.2452795782. The cubic root of 6405000221 is about 1857.1189277849.

Adding to 6405000221 its reverse (1220005046), we get a palindrome (7625005267).

The spelling of 6405000221 in words is "six billion, four hundred five million, two hundred twenty-one", and thus it is an aban number.