9999980076646 has 24 divisors (see below), whose sum is σ = 17449713463896. Its totient is φ = 4285516959360.

The previous prime is 9999980076523. The next prime is 9999980076659. The reversal of 9999980076646 is 6466700899999.

9999980076646 is a nontrivial binomial coefficient, being equal to C(4472132, 2).

It is a self number, because there is not a number n which added to its sum of digits gives 9999980076646.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 1 + ... + 4472131.

It is an arithmetic number, because the mean of its divisors is an integer number (727071394329).

Almost surely, 2^{9999980076646} is an apocalyptic number.

9999980076646 is the 4472131-st triangular number and also the 2236066-th hexagonal number.

9999980076646 is the 1490711-st centered nonagonal number.

9999980076646 is a deficient number, since it is larger than the sum of its proper divisors (7449733387250).

9999980076646 is a wasteful number, since it uses less digits than its factorization.

9999980076646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4494964 (or 4494957 counting only the distinct ones).

The product of its (nonzero) digits is 2857026816, while the sum is 82.

The spelling of 9999980076646 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred eighty million, seventy-six thousand, six hundred forty-six".