216696512519666 has 8 divisors (see below), whose sum is σ = 325073324095104. Its totient is φ = 108338737821300.

The previous prime is 216696512519657. The next prime is 216696512519701. The reversal of 216696512519666 is 666915215696612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216696512519666.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4759190810 + ... + 4759236341.

It is an arithmetic number, because the mean of its divisors is an integer number (40634165511888).

Almost surely, 2^{216696512519666} is an apocalyptic number.

216696512519666 is a deficient number, since it is larger than the sum of its proper divisors (108376811575438).

216696512519666 is a wasteful number, since it uses less digits than its factorization.

216696512519666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9518438536.

The product of its digits is 377913600, while the sum is 71.

The spelling of 216696512519666 in words is "two hundred sixteen trillion, six hundred ninety-six billion, five hundred twelve million, five hundred nineteen thousand, six hundred sixty-six".