9921994560 has 280 divisors, whose sum is σ = 37153717920. Its totient is φ = 2506484736.

The previous prime is 9921994559. The next prime is 9921994591. The reversal of 9921994560 is 654991299.

9921994560 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 9921994497 and 9921994506.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 482407 + ... + 502553.

Almost surely, 2^9921994560 is an apocalyptic number.

9921994560 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9921994560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18576858960).

9921994560 is an abundant number, since it is smaller than the sum of its proper divisors (27231723360).

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

9921994560 is a wasteful number, since it uses less digits than its factorization.

9921994560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20195 (or 20176 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 54.

The square root of 9921994560 is about 99609.2092128032. The cubic root of 9921994560 is about 2148.8181397030.

The spelling of 9921994560 in words is "nine billion, nine hundred twenty-one million, nine hundred ninety-four thousand, five hundred sixty".