6666940757 has 2 divisors, whose sum is σ = 6666940758. Its totient is φ = 6666940756.

The previous prime is 6666940727. The next prime is 6666940801. The reversal of 6666940757 is 7570496666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6449053636 + 217887121 = 80306^2 + 14761^2 .

It is a cyclic number.

It is not a de Polignac number, because 6666940757 - 2¹⁴ = 6666924373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6666940727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3333470378 + 3333470379.

It is an arithmetic number, because the mean of its divisors is an integer number (3333470379).

Almost surely, 2^6666940757 is an apocalyptic number.

It is an amenable number.

6666940757 is a deficient number, since it is larger than the sum of its proper divisors (1).

6666940757 is an equidigital number, since it uses as much as digits as its factorization.

6666940757 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11430720, while the sum is 56.

The square root of 6666940757 is about 81651.3365291714. The cubic root of 6666940757 is about 1882.0978502965.

The spelling of 6666940757 in words is "six billion, six hundred sixty-six million, nine hundred forty thousand, seven hundred fifty-seven".