646821674168 has 32 divisors (see below), whose sum is σ = 1214575536000. Its totient is φ = 322935141600.

The previous prime is 646821674131. The next prime is 646821674189. The reversal of 646821674168 is 861476128646.

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, 20945123 + ... + 20975981.

It is an arithmetic number, because the mean of its divisors is an integer number (37955485500).

Almost surely, 2^646821674168 is an apocalyptic number.

It is an amenable number.

646821674168 is a deficient number, since it is larger than the sum of its proper divisors (567753861832).

646821674168 is a wasteful number, since it uses less digits than its factorization.

646821674168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34635 (or 34631 counting only the distinct ones).

The product of its digits is 18579456, while the sum is 59.

The spelling of 646821674168 in words is "six hundred forty-six billion, eight hundred twenty-one million, six hundred seventy-four thousand, one hundred sixty-eight".