21959421120 has 672 divisors, whose sum is σ = 97029983232. Its totient is φ = 4430536704.

The previous prime is 21959421103. The next prime is 21959421163. The reversal of 21959421120 is 2112495912.

21959421120 is a `hidden beast` number, since 21 + 9 + 594 + 21 + 1 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6026019 + ... + 6029661.

It is an arithmetic number, because the mean of its divisors is an integer number (144389856).

Almost surely, 2^21959421120 is an apocalyptic number.

21959421120 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 21959421120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48514991616).

21959421120 is an abundant number, since it is smaller than the sum of its proper divisors (75070562112).

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

21959421120 is a wasteful number, since it uses less digits than its factorization.

21959421120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3709 (or 3696 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 21959421120 in words is "twenty-one billion, nine hundred fifty-nine million, four hundred twenty-one thousand, one hundred twenty".