9921055680 has 168 divisors, whose sum is σ = 35046952512. Its totient is φ = 2574084096.

The previous prime is 9921055679. The next prime is 9921055691. The reversal of 9921055680 is 865501299.

9921055680 is a `hidden beast` number, since 9 + 9 + 2 + 10 + 556 + 80 = 666.

9921055680 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 (45).

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 23 ways as a sum of consecutive naturals, for example, 60009 + ... + 153111.

Almost surely, 2^9921055680 is an apocalyptic number.

9921055680 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 9921055680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17523476256).

9921055680 is an abundant number, since it is smaller than the sum of its proper divisors (25125896832).

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

9921055680 is a wasteful number, since it uses less digits than its factorization.

9921055680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93163 (or 93150 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The square root of 9921055680 is about 99604.4962840534. The cubic root of 9921055680 is about 2148.7503594463.

The spelling of 9921055680 in words is "nine billion, nine hundred twenty-one million, fifty-five thousand, six hundred eighty".