8681646544 has 20 divisors (see below), whose sum is σ = 16917924996. Its totient is φ = 4315730432.

The previous prime is 8681646529. The next prime is 8681646563. The reversal of 8681646544 is 4456461868.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 8301396544 + 380250000 = 91112^2 + 19500^2 .

It is a junction number, because it is equal to n+sod(n) for n = 8681646491 and 8681646500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1565449 + ... + 1570984.

Almost surely, 2^8681646544 is an apocalyptic number.

It is an amenable number.

8681646544 is a deficient number, since it is larger than the sum of its proper divisors (8236278452).

8681646544 is a wasteful number, since it uses less digits than its factorization.

8681646544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3136614 (or 3136608 counting only the distinct ones).

The product of its digits is 4423680, while the sum is 52.

The square root of 8681646544 is about 93175.3537369191. The cubic root of 8681646544 is about 2055.2628244859.

The spelling of 8681646544 in words is "eight billion, six hundred eighty-one million, six hundred forty-six thousand, five hundred forty-four".