21815720960000 has 1680 divisors, whose sum is σ = 66689204685840. Its totient is φ = 7060193280000.

The previous prime is 21815720959999. The next prime is 21815720960009. The reversal of 21815720960000 is 6902751812.

It is a self number, because there is not a number n which added to its sum of digits gives 21815720960000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21815720960009) by changing a digit.

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 119 ways as a sum of consecutive naturals, for example, 589614079982 + ... + 589614080018.

Almost surely, 2^{21815720960000} is an apocalyptic number.

21815720960000 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 21815720960000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33344602342920).

21815720960000 is an abundant number, since it is smaller than the sum of its proper divisors (44873483725840).

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

21815720960000 is an equidigital number, since it uses as much as digits as its factorization.

21815720960000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 41.

The spelling of 21815720960000 in words is "twenty-one trillion, eight hundred fifteen billion, seven hundred twenty million, nine hundred sixty thousand".