21691943719680 has 1152 divisors, whose sum is σ = 77778057240576. Its totient is φ = 5118433689600.

The previous prime is 21691943719673. The next prime is 21691943719759. The reversal of 21691943719680 is 8691734919612.

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 127 ways as a sum of consecutive naturals, for example, 32816858550 + ... + 32816859210.

It is an arithmetic number, because the mean of its divisors is an integer number (67515674688).

Almost surely, 2^{21691943719680} is an apocalyptic number.

21691943719680 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 21691943719680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38889028620288).

21691943719680 is an abundant number, since it is smaller than the sum of its proper divisors (56086113520896).

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

21691943719680 is a wasteful number, since it uses less digits than its factorization.

21691943719680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013 (or 999 counting only the distinct ones).

The product of its (nonzero) digits is 35271936, while the sum is 66.

The spelling of 21691943719680 in words is "twenty-one trillion, six hundred ninety-one billion, nine hundred forty-three million, seven hundred nineteen thousand, six hundred eighty".