6666766693 has 2 divisors, whose sum is σ = 6666766694. Its totient is φ = 6666766692.

The previous prime is 6666766681. The next prime is 6666766697. The reversal of 6666766693 is 3966676666.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6525085284 + 141681409 = 80778^2 + 11903^2 .

It is a cyclic number.

It is not a de Polignac number, because 6666766693 - 2²¹ = 6664669541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6666766697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3333383346 + 3333383347.

It is an arithmetic number, because the mean of its divisors is an integer number (3333383347).

Almost surely, 2^6666766693 is an apocalyptic number.

It is an amenable number.

6666766693 is a deficient number, since it is larger than the sum of its proper divisors (1).

6666766693 is an equidigital number, since it uses as much as digits as its factorization.

6666766693 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52907904, while the sum is 61.

The square root of 6666766693 is about 81650.2706241688. The cubic root of 6666766693 is about 1882.0814705533.

The spelling of 6666766693 in words is "six billion, six hundred sixty-six million, seven hundred sixty-six thousand, six hundred ninety-three".