216668866866 has 32 divisors (see below), whose sum is σ = 447869606400. Its totient is φ = 69806739840.

The previous prime is 216668866861. The next prime is 216668866901. The reversal of 216668866866 is 668668866612.

It is a self number, because there is not a number n which added to its sum of digits gives 216668866866.

It is not an unprimeable number, because it can be changed into a prime (216668866861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 569481 + ... + 870428.

It is an arithmetic number, because the mean of its divisors is an integer number (13995925200).

Almost surely, 2^216668866866 is an apocalyptic number.

216668866866 is an abundant number, since it is smaller than the sum of its proper divisors (231200739534).

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

216668866866 is a wasteful number, since it uses less digits than its factorization.

216668866866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1440754.

The product of its digits is 286654464, while the sum is 69.

The spelling of 216668866866 in words is "two hundred sixteen billion, six hundred sixty-eight million, eight hundred sixty-six thousand, eight hundred sixty-six".