21985755348480 has 640 divisors, whose sum is σ = 87693631534080. Its totient is φ = 4565096202240.

The previous prime is 21985755348467. The next prime is 21985755348503. The reversal of 21985755348480 is 8484355758912.

It is a tau number, because it is divible by the number of its divisors (640).

It is a super-3 number, since 3×21985755348480³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 845040432 + ... + 845066448.

It is an arithmetic number, because the mean of its divisors is an integer number (137021299272).

Almost surely, 2^{21985755348480} is an apocalyptic number.

21985755348480 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 21985755348480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43846815767040).

21985755348480 is an abundant number, since it is smaller than the sum of its proper divisors (65707876185600).

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

21985755348480 is a wasteful number, since it uses less digits than its factorization.

21985755348480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27490 (or 27474 counting only the distinct ones).

The product of its (nonzero) digits is 387072000, while the sum is 69.

The spelling of 21985755348480 in words is "twenty-one trillion, nine hundred eighty-five billion, seven hundred fifty-five million, three hundred forty-eight thousand, four hundred eighty".