21159895680 has 1792 divisors, whose sum is σ = 102745497600. Its totient is φ = 4031078400.

The previous prime is 21159895667. The next prime is 21159895723. The reversal of 21159895680 is 8659895112.

21159895680 is a `hidden beast` number, since 21 + 1 + 59 + 8 + 9 + 568 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 682577265 + ... + 682577295.

Almost surely, 2^21159895680 is an apocalyptic number.

21159895680 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 21159895680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51372748800).

21159895680 is an abundant number, since it is smaller than the sum of its proper divisors (81585601920).

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

21159895680 is a wasteful number, since it uses less digits than its factorization.

21159895680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 54.

The spelling of 21159895680 in words is "twenty-one billion, one hundred fifty-nine million, eight hundred ninety-five thousand, six hundred eighty".