7806646666 has 16 divisors (see below), whose sum is σ = 14412271104. Its totient is φ = 3088343664.

The previous prime is 7806646657. The next prime is 7806646681. The reversal of 7806646666 is 6666466087.

It is a super-3 number, since 3×7806646666³ (a number of 31 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21446650 + ... + 21447013.

It is an arithmetic number, because the mean of its divisors is an integer number (900766944).

Almost surely, 2^7806646666 is an apocalyptic number.

7806646666 is a deficient number, since it is larger than the sum of its proper divisors (6605624438).

7806646666 is a wasteful number, since it uses less digits than its factorization.

7806646666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42893685.

The product of its (nonzero) digits is 10450944, while the sum is 55.

The square root of 7806646666 is about 88355.2299866850. The cubic root of 7806646666 is about 1983.7556397593.

The spelling of 7806646666 in words is "seven billion, eight hundred six million, six hundred forty-six thousand, six hundred sixty-six".