21590664775680 has 4608 divisors, whose sum is σ = 101190220185600. Its totient is φ = 3814981632000.

The previous prime is 21590664775663. The next prime is 21590664775681. The reversal of 21590664775680 is 8657746609512.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is not an unprimeable number, because it can be changed into a prime (21590664775681) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 304093870045 + ... + 304093870115.

It is an arithmetic number, because the mean of its divisors is an integer number (21959683200).

Almost surely, 2^{21590664775680} is an apocalyptic number.

21590664775680 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 21590664775680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50595110092800).

21590664775680 is an abundant number, since it is smaller than the sum of its proper divisors (79599555409920).

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

21590664775680 is a wasteful number, since it uses less digits than its factorization.

21590664775680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203 (or 172 counting only the distinct ones).

The product of its (nonzero) digits is 152409600, while the sum is 66.

The spelling of 21590664775680 in words is "twenty-one trillion, five hundred ninety billion, six hundred sixty-four million, seven hundred seventy-five thousand, six hundred eighty".