866189945826 has 24 divisors (see below), whose sum is σ = 1900501150080. Its totient is φ = 285075171576.

The previous prime is 866189945779. The next prime is 866189945851. The reversal of 866189945826 is 628549981668.

866189945826 is a `hidden beast` number, since 8 + 6 + 61 + 8 + 99 + 458 + 26 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 304566070 + ... + 304568913.

It is an arithmetic number, because the mean of its divisors is an integer number (79187547920).

Almost surely, 2^866189945826 is an apocalyptic number.

866189945826 is an abundant number, since it is smaller than the sum of its proper divisors (1034311204254).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866189945826 is a wasteful number, since it uses less digits than its factorization.

866189945826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 609135070 (or 609135067 counting only the distinct ones).

The product of its digits is 358318080, while the sum is 72.

The spelling of 866189945826 in words is "eight hundred sixty-six billion, one hundred eighty-nine million, nine hundred forty-five thousand, eight hundred twenty-six".