6637066561 has 2 divisors, whose sum is σ = 6637066562. Its totient is φ = 6637066560.

The previous prime is 6637066537. The next prime is 6637066589. The reversal of 6637066561 is 1656607366.

6637066561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4921864336 + 1715202225 = 70156^2 + 41415^2 .

It is a cyclic number.

It is not a de Polignac number, because 6637066561 - 2¹⁹ = 6636542273 is a prime.

It is not a weakly prime, because it can be changed into another prime (6637066591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3318533280 + 3318533281.

It is an arithmetic number, because the mean of its divisors is an integer number (3318533281).

Almost surely, 2^6637066561 is an apocalyptic number.

It is an amenable number.

6637066561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6637066561 is an equidigital number, since it uses as much as digits as its factorization.

6637066561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 816480, while the sum is 46.

The square root of 6637066561 is about 81468.1935542945. The cubic root of 6637066561 is about 1879.2824484538.

The spelling of 6637066561 in words is "six billion, six hundred thirty-seven million, sixty-six thousand, five hundred sixty-one".