21843471720 has 256 divisors, whose sum is σ = 78373601280. Its totient is φ = 4765132800.

The previous prime is 21843471719. The next prime is 21843471791. The reversal of 21843471720 is 2717434812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1895175 + ... + 1906665.

It is an arithmetic number, because the mean of its divisors is an integer number (306146880).

Almost surely, 2^21843471720 is an apocalyptic number.

21843471720 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 21843471720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39186800640).

21843471720 is an abundant number, since it is smaller than the sum of its proper divisors (56530129560).

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

21843471720 is a wasteful number, since it uses less digits than its factorization.

21843471720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11616 (or 11612 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 39.

The spelling of 21843471720 in words is "twenty-one billion, eight hundred forty-three million, four hundred seventy-one thousand, seven hundred twenty".