84805981866 has 12 divisors (see below), whose sum is σ = 183746294082. Its totient is φ = 28268660616.

The previous prime is 84805981861. The next prime is 84805981921. The reversal of 84805981866 is 66818950848.

84805981866 is a `hidden beast` number, since 8 + 480 + 5 + 98 + 1 + 8 + 66 = 666.

It can be written as a sum of positive squares in only one way, i.e., 81066047841 + 3739934025 = 284721^2 + 61155^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (84805981861) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2355721701 + ... + 2355721736.

Almost surely, 2^84805981866 is an apocalyptic number.

84805981866 is an abundant number, since it is smaller than the sum of its proper divisors (98940312216).

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

84805981866 is a wasteful number, since it uses less digits than its factorization.

84805981866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4711443445 (or 4711443442 counting only the distinct ones).

The product of its (nonzero) digits is 26542080, while the sum is 63.

The spelling of 84805981866 in words is "eighty-four billion, eight hundred five million, nine hundred eighty-one thousand, eight hundred sixty-six".