21120984960 has 256 divisors, whose sum is σ = 72194457600. Its totient is φ = 5233213440.

The previous prime is 21120984959. The next prime is 21120984967. The reversal of 21120984960 is 6948902112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120984967) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2574465 + ... + 2582655.

It is an arithmetic number, because the mean of its divisors is an integer number (282009600).

Almost surely, 2^21120984960 is an apocalyptic number.

21120984960 is a gapful number since it is divisible by the number (20) 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 21120984960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36097228800).

21120984960 is an abundant number, since it is smaller than the sum of its proper divisors (51073472640).

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

21120984960 is a wasteful number, since it uses less digits than its factorization.

21120984960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8309 (or 8297 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 42.

The spelling of 21120984960 in words is "twenty-one billion, one hundred twenty million, nine hundred eighty-four thousand, nine hundred sixty".