9919681568 has 48 divisors (see below), whose sum is σ = 20205158400. Its totient is φ = 4788940800.

The previous prime is 9919681553. The next prime is 9919681589. The reversal of 9919681568 is 8651869199.

It is a Harshad number since it is a multiple of its sum of digits (62).

It is a self number, because there is not a number n which added to its sum of digits gives 9919681568.

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, 434273 + ... + 456543.

It is an arithmetic number, because the mean of its divisors is an integer number (420940800).

Almost surely, 2^9919681568 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9919681568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10102579200).

9919681568 is an abundant number, since it is smaller than the sum of its proper divisors (10285476832).

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

9919681568 is a wasteful number, since it uses less digits than its factorization.

9919681568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22761 (or 22753 counting only the distinct ones).

The product of its digits is 8398080, while the sum is 62.

The square root of 9919681568 is about 99597.5982039728. The cubic root of 9919681568 is about 2148.6511509186.

The spelling of 9919681568 in words is "nine billion, nine hundred nineteen million, six hundred eighty-one thousand, five hundred sixty-eight".