6662606353561 has 2 divisors, whose sum is σ = 6662606353562. Its totient is φ = 6662606353560.

The previous prime is 6662606353411. The next prime is 6662606353591. The reversal of 6662606353561 is 1653536062666.

6662606353561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5092988265225 + 1569618088336 = 2256765^2 + 1252844^2 .

It is a cyclic number.

It is not a de Polignac number, because 6662606353561 - 2⁹ = 6662606353049 is a prime.

It is a super-2 number, since 2×6662606353561² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6662606353591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3331303176780 + 3331303176781.

It is an arithmetic number, because the mean of its divisors is an integer number (3331303176781).

Almost surely, 2^{6662606353561} is an apocalyptic number.

It is an amenable number.

6662606353561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6662606353561 is an equidigital number, since it uses as much as digits as its factorization.

6662606353561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20995200, while the sum is 55.

The spelling of 6662606353561 in words is "six trillion, six hundred sixty-two billion, six hundred six million, three hundred fifty-three thousand, five hundred sixty-one".