21843851904 has 960 divisors, whose sum is σ = 83293689600. Its totient is φ = 5643509760.

The previous prime is 21843851881. The next prime is 21843851963. The reversal of 21843851904 is 40915834812.

21843851904 is a `hidden beast` number, since 2 + 1 + 84 + 385 + 190 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21843851904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 299230812 + ... + 299230884.

It is an arithmetic number, because the mean of its divisors is an integer number (86764260).

Almost surely, 2^21843851904 is an apocalyptic number.

21843851904 is a gapful number since it is divisible by the number (24) 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 21843851904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41646844800).

21843851904 is an abundant number, since it is smaller than the sum of its proper divisors (61449837696).

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

21843851904 is a wasteful number, since it uses less digits than its factorization.

21843851904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 135 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 21843851904 in words is "twenty-one billion, eight hundred forty-three million, eight hundred fifty-one thousand, nine hundred four".