21059918880 has 768 divisors, whose sum is σ = 90860507136. Its totient is φ = 3958456320.

The previous prime is 21059918879. The next prime is 21059918939. The reversal of 21059918880 is 8881995012.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 25465027 + ... + 25465853.

It is an arithmetic number, because the mean of its divisors is an integer number (118307952).

Almost surely, 2^21059918880 is an apocalyptic number.

21059918880 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 21059918880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45430253568).

21059918880 is an abundant number, since it is smaller than the sum of its proper divisors (69800588256).

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

21059918880 is a wasteful number, since it uses less digits than its factorization.

21059918880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 929 (or 921 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 51.

It can be divided in two parts, 21059 and 918880, that added together give a palindrome (939939).

The spelling of 21059918880 in words is "twenty-one billion, fifty-nine million, nine hundred eighteen thousand, eight hundred eighty".