866786278381166 has 64 divisors (see below), whose sum is σ = 1608061499493120. Its totient is φ = 344505698933760.

The previous prime is 866786278381091. The next prime is 866786278381181. The reversal of 866786278381166 is 661183872687668.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38348345 + ... + 56605371.

It is an arithmetic number, because the mean of its divisors is an integer number (25125960929580).

Almost surely, 2^{866786278381166} is an apocalyptic number.

866786278381166 is a deficient number, since it is larger than the sum of its proper divisors (741275221111954).

866786278381166 is a wasteful number, since it uses less digits than its factorization.

866786278381166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18265809.

The product of its digits is 9364045824, while the sum is 83.

The spelling of 866786278381166 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, two hundred seventy-eight million, three hundred eighty-one thousand, one hundred sixty-six".