6506900221 has 2 divisors, whose sum is σ = 6506900222. Its totient is φ = 6506900220.

The previous prime is 6506900219. The next prime is 6506900243. The reversal of 6506900221 is 1220096056.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5320097721 + 1186802500 = 72939^2 + 34450^2 .

It is a cyclic number.

It is not a de Polignac number, because 6506900221 - 2¹ = 6506900219 is a prime.

Together with 6506900219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6506900021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3253450110 + 3253450111.

It is an arithmetic number, because the mean of its divisors is an integer number (3253450111).

Almost surely, 2^6506900221 is an apocalyptic number.

It is an amenable number.

6506900221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6506900221 is an equidigital number, since it uses as much as digits as its factorization.

6506900221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 6506900221 is about 80665.3594859652. The cubic root of 6506900221 is about 1866.9157333723.

Adding to 6506900221 its reverse (1220096056), we get a palindrome (7726996277).

The spelling of 6506900221 in words is "six billion, five hundred six million, nine hundred thousand, two hundred twenty-one".