21859484544 has 384 divisors, whose sum is σ = 68739840000. Its totient is φ = 6642155520.

The previous prime is 21859484531. The next prime is 21859484611. The reversal of 21859484544 is 44548495812.

21859484544 is a `hidden beast` number, since 2 + 1 + 8 + 5 + 94 + 8 + 4 + 544 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 109846557 + ... + 109846755.

It is an arithmetic number, because the mean of its divisors is an integer number (179010000).

Almost surely, 2^21859484544 is an apocalyptic number.

21859484544 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 21859484544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34369920000).

21859484544 is an abundant number, since it is smaller than the sum of its proper divisors (46880355456).

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

21859484544 is a wasteful number, since it uses less digits than its factorization.

21859484544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 371 counting only the distinct ones).

The product of its digits is 7372800, while the sum is 54.

The spelling of 21859484544 in words is "twenty-one billion, eight hundred fifty-nine million, four hundred eighty-four thousand, five hundred forty-four".