1216006666 has 32 divisors (see below), whose sum is σ = 2133112320. Its totient is φ = 509099136.

The previous prime is 1216006643. The next prime is 1216006679. The reversal of 1216006666 is 6666006121.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173910 + ... + 180766.

It is an arithmetic number, because the mean of its divisors is an integer number (66659760).

Almost surely, 2^1216006666 is an apocalyptic number.

1216006666 is a deficient number, since it is larger than the sum of its proper divisors (917105654).

1216006666 is a wasteful number, since it uses less digits than its factorization.

1216006666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7158.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 1216006666 is about 34871.2871285245. The cubic root of 1216006666 is about 1067.3626098762.

The spelling of 1216006666 in words is "one billion, two hundred sixteen million, six thousand, six hundred sixty-six".