21171145588560 has 720 divisors, whose sum is σ = 81145205249472. Its totient is φ = 5126083522560.

The previous prime is 21171145588513. The next prime is 21171145588589. The reversal of 21171145588560 is 6588554117112.

21171145588560 is a `hidden beast` number, since 2 + 1 + 1 + 7 + 1 + 1 + 4 + 5 + 588 + 56 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 21171145588497 and 21171145588506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2077022824 + ... + 2077033016.

Almost surely, 2^{21171145588560} is an apocalyptic number.

21171145588560 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 21171145588560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40572602624736).

21171145588560 is an abundant number, since it is smaller than the sum of its proper divisors (59974059660912).

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

21171145588560 is a wasteful number, since it uses less digits than its factorization.

21171145588560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11126 (or 11097 counting only the distinct ones).

The product of its (nonzero) digits is 2688000, while the sum is 54.

The spelling of 21171145588560 in words is "twenty-one trillion, one hundred seventy-one billion, one hundred forty-five million, five hundred eighty-eight thousand, five hundred sixty".