6521221297 has 2 divisors, whose sum is σ = 6521221298. Its totient is φ = 6521221296.

The previous prime is 6521221253. The next prime is 6521221309. The reversal of 6521221297 is 7921221256.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6470754481 + 50466816 = 80441^2 + 7104^2 .

It is a cyclic number.

It is not a de Polignac number, because 6521221297 - 2²⁷ = 6387003569 is a prime.

It is not a weakly prime, because it can be changed into another prime (6521221397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3260610648 + 3260610649.

It is an arithmetic number, because the mean of its divisors is an integer number (3260610649).

Almost surely, 2^6521221297 is an apocalyptic number.

It is an amenable number.

6521221297 is a deficient number, since it is larger than the sum of its proper divisors (1).

6521221297 is an equidigital number, since it uses as much as digits as its factorization.

6521221297 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 37.

The square root of 6521221297 is about 80754.0791353601. The cubic root of 6521221297 is about 1868.2843651577.

The spelling of 6521221297 in words is "six billion, five hundred twenty-one million, two hundred twenty-one thousand, two hundred ninety-seven".