16666566655 has 16 divisors (see below), whose sum is σ = 20699712000. Its totient is φ = 12867151360.

The previous prime is 16666566649. The next prime is 16666566689. The reversal of 16666566655 is 55666566661.

It is not a de Polignac number, because 16666566655 - 2⁹ = 16666566143 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16666566655.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278871 + ... + 333319.

It is an arithmetic number, because the mean of its divisors is an integer number (1293732000).

Almost surely, 2^16666566655 is an apocalyptic number.

16666566655 is a deficient number, since it is larger than the sum of its proper divisors (4033145345).

16666566655 is a wasteful number, since it uses less digits than its factorization.

16666566655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56594.

The product of its digits is 34992000, while the sum is 58.

The spelling of 16666566655 in words is "sixteen billion, six hundred sixty-six million, five hundred sixty-six thousand, six hundred fifty-five".