666261527812319 has 2 divisors, whose sum is σ = 666261527812320. Its totient is φ = 666261527812318.

The previous prime is 666261527812301. The next prime is 666261527812373. The reversal of 666261527812319 is 913218725162666.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666261527812319 is a prime.

It is a super-2 number, since 2×666261527812319² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666261527812619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333130763906159 + 333130763906160.

It is an arithmetic number, because the mean of its divisors is an integer number (333130763906160).

Almost surely, 2^{666261527812319} is an apocalyptic number.

666261527812319 is a deficient number, since it is larger than the sum of its proper divisors (1).

666261527812319 is an equidigital number, since it uses as much as digits as its factorization.

666261527812319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78382080, while the sum is 65.

The spelling of 666261527812319 in words is "six hundred sixty-six trillion, two hundred sixty-one billion, five hundred twenty-seven million, eight hundred twelve thousand, three hundred nineteen".