866130377871681 has 12 divisors (see below), whose sum is σ = 1347313921133908. Its totient is φ = 533003309459424.

The previous prime is 866130377871617. The next prime is 866130377871683. The reversal of 866130377871681 is 186178773031668.

866130377871681 is a `hidden beast` number, since 8 + 6 + 6 + 13 + 0 + 377 + 87 + 168 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 265363806780081 + 600766571091600 = 16289991^2 + 24510540^2 .

It is not a de Polignac number, because 866130377871681 - 2⁶ = 866130377871617 is a prime.

It is a super-4 number, since 4×866130377871681⁴ (a number of 61 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (866130377871683) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3701411871130 + ... + 3701411871363.

Almost surely, 2^{866130377871681} is an apocalyptic number.

It is an amenable number.

866130377871681 is a deficient number, since it is larger than the sum of its proper divisors (481183543262227).

866130377871681 is a wasteful number, since it uses less digits than its factorization.

866130377871681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7402823742512 (or 7402823742509 counting only the distinct ones).

The product of its (nonzero) digits is 341397504, while the sum is 72.

The spelling of 866130377871681 in words is "eight hundred sixty-six trillion, one hundred thirty billion, three hundred seventy-seven million, eight hundred seventy-one thousand, six hundred eighty-one".