21159444240 has 480 divisors, whose sum is σ = 84346684800. Its totient is φ = 4858444800.

The previous prime is 21159444223. The next prime is 21159444263. The reversal of 21159444240 is 4244495112.

21159444240 is a `hidden beast` number, since 2 + 1 + 1 + 594 + 44 + 24 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 21159444195 and 21159444204.

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 95 ways as a sum of consecutive naturals, for example, 4963710 + ... + 4967970.

It is an arithmetic number, because the mean of its divisors is an integer number (175722260).

Almost surely, 2^21159444240 is an apocalyptic number.

21159444240 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 21159444240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42173342400).

21159444240 is an abundant number, since it is smaller than the sum of its proper divisors (63187240560).

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

21159444240 is a wasteful number, since it uses less digits than its factorization.

21159444240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4324 (or 4301 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 21159444240 in words is "twenty-one billion, one hundred fifty-nine million, four hundred forty-four thousand, two hundred forty".