6643669678 has 16 divisors (see below), whose sum is σ = 10414229760. Its totient is φ = 3175547256.

The previous prime is 6643669639. The next prime is 6643669693. The reversal of 6643669678 is 8769663466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 817788 + ... + 825871.

It is an arithmetic number, because the mean of its divisors is an integer number (650889360).

Almost surely, 2^6643669678 is an apocalyptic number.

6643669678 is a deficient number, since it is larger than the sum of its proper divisors (3770560082).

6643669678 is a wasteful number, since it uses less digits than its factorization.

6643669678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643751.

The product of its digits is 47029248, while the sum is 61.

The square root of 6643669678 is about 81508.7092156415. The cubic root of 6643669678 is about 1879.9054651046.

The spelling of 6643669678 in words is "six billion, six hundred forty-three million, six hundred sixty-nine thousand, six hundred seventy-eight".