9891638064 has 120 divisors (see below), whose sum is σ = 34513719552. Its totient is φ = 2569253760.

The previous prime is 9891638047. The next prime is 9891638077. The reversal of 9891638064 is 4608361989.

It is a self number, because there is not a number n which added to its sum of digits gives 9891638064.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 434964 + ... + 457139.

Almost surely, 2^9891638064 is an apocalyptic number.

It is an amenable number.

9891638064 is an abundant number, since it is smaller than the sum of its proper divisors (24622081488).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9891638064 is a wasteful number, since it uses less digits than its factorization.

9891638064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 892135 (or 892126 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The square root of 9891638064 is about 99456.7145244603. The cubic root of 9891638064 is about 2146.6244535162.

The spelling of 9891638064 in words is "nine billion, eight hundred ninety-one million, six hundred thirty-eight thousand, sixty-four".