866786278586441 has 2 divisors, whose sum is σ = 866786278586442. Its totient is φ = 866786278586440.

The previous prime is 866786278586399. The next prime is 866786278586497. The reversal of 866786278586441 is 144685872687668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 836263968496441 + 30522310090000 = 28918229^2 + 5524700^2 .

It is a cyclic number.

It is not a de Polignac number, because 866786278586441 - 2¹⁴ = 866786278570057 is a prime.

It is not a weakly prime, because it can be changed into another prime (866786278583441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433393139293220 + 433393139293221.

It is an arithmetic number, because the mean of its divisors is an integer number (433393139293221).

Almost surely, 2^{866786278586441} is an apocalyptic number.

It is an amenable number.

866786278586441 is a deficient number, since it is larger than the sum of its proper divisors (1).

866786278586441 is an equidigital number, since it uses as much as digits as its factorization.

866786278586441 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41617981440, while the sum is 86.

The spelling of 866786278586441 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, two hundred seventy-eight million, five hundred eighty-six thousand, four hundred forty-one".