21303116705680 has 80 divisors (see below), whose sum is σ = 52153901668800. Its totient is φ = 8070077191680.

The previous prime is 21303116705677. The next prime is 21303116705693. The reversal of 21303116705680 is 8650761130312.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2249386 + ... + 6904054.

It is an arithmetic number, because the mean of its divisors is an integer number (651923770860).

Almost surely, 2^{21303116705680} is an apocalyptic number.

21303116705680 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 21303116705680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26076950834400).

21303116705680 is an abundant number, since it is smaller than the sum of its proper divisors (30850784963120).

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

21303116705680 is a wasteful number, since it uses less digits than its factorization.

21303116705680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4657712 (or 4657706 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 43.

Adding to 21303116705680 its reverse (8650761130312), we get a palindrome (29953877835992).

The spelling of 21303116705680 in words is "twenty-one trillion, three hundred three billion, one hundred sixteen million, seven hundred five thousand, six hundred eighty".