666242140877 has 2 divisors, whose sum is σ = 666242140878. Its totient is φ = 666242140876.

The previous prime is 666242140813. The next prime is 666242140897. The reversal of 666242140877 is 778041242666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 664345625476 + 1896515401 = 815074^2 + 43549^2 .

It is a cyclic number.

It is not a de Polignac number, because 666242140877 - 2⁶ = 666242140813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666242140897) 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, 333121070438 + 333121070439.

It is an arithmetic number, because the mean of its divisors is an integer number (333121070439).

Almost surely, 2^666242140877 is an apocalyptic number.

It is an amenable number.

666242140877 is a deficient number, since it is larger than the sum of its proper divisors (1).

666242140877 is an equidigital number, since it uses as much as digits as its factorization.

666242140877 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5419008, while the sum is 53.

The spelling of 666242140877 in words is "six hundred sixty-six billion, two hundred forty-two million, one hundred forty thousand, eight hundred seventy-seven".