6561349841 has 2 divisors, whose sum is σ = 6561349842. Its totient is φ = 6561349840.

The previous prime is 6561349807. The next prime is 6561349853. The reversal of 6561349841 is 1489431656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3380841025 + 3180508816 = 58145^2 + 56396^2 .

It is a cyclic number.

It is not a de Polignac number, because 6561349841 - 2⁶ = 6561349777 is a prime.

It is not a weakly prime, because it can be changed into another prime (6561349141) 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, 3280674920 + 3280674921.

It is an arithmetic number, because the mean of its divisors is an integer number (3280674921).

Almost surely, 2^6561349841 is an apocalyptic number.

It is an amenable number.

6561349841 is a deficient number, since it is larger than the sum of its proper divisors (1).

6561349841 is an equidigital number, since it uses as much as digits as its factorization.

6561349841 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 622080, while the sum is 47.

The square root of 6561349841 is about 81002.1594835594. The cubic root of 6561349841 is about 1872.1087139827.

The spelling of 6561349841 in words is "six billion, five hundred sixty-one million, three hundred forty-nine thousand, eight hundred forty-one".