666140615747797 has 2 divisors, whose sum is σ = 666140615747798. Its totient is φ = 666140615747796.

The previous prime is 666140615747741. The next prime is 666140615747807. The reversal of 666140615747797 is 797747516041666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 346654090585201 + 319486525162596 = 18618649^2 + 17874186^2 .

It is a cyclic number.

It is not a de Polignac number, because 666140615747797 - 2⁷ = 666140615747669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666140615147797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333070307873898 + 333070307873899.

It is an arithmetic number, because the mean of its divisors is an integer number (333070307873899).

Almost surely, 2^{666140615747797} is an apocalyptic number.

It is an amenable number.

666140615747797 is a deficient number, since it is larger than the sum of its proper divisors (1).

666140615747797 is an equidigital number, since it uses as much as digits as its factorization.

666140615747797 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2240421120, while the sum is 76.

The spelling of 666140615747797 in words is "six hundred sixty-six trillion, one hundred forty billion, six hundred fifteen million, seven hundred forty-seven thousand, seven hundred ninety-seven".