21171506982048 has 216 divisors, whose sum is σ = 62535413592288. Its totient is φ = 7055308469376.

The previous prime is 21171506982037. The next prime is 21171506982077. The reversal of 21171506982048 is 84028960517112.

21171506982048 is a `hidden beast` number, since 2 + 1 + 1 + 7 + 1 + 506 + 98 + 2 + 0 + 48 = 666.

It is a tau number, because it is divible by the number of its divisors (216).

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 = 21171506981985 and 21171506982003.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 962199015 + ... + 962221017.

It is an arithmetic number, because the mean of its divisors is an integer number (289515803668).

Almost surely, 2^{21171506982048} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21171506982048, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31267706796144).

21171506982048 is an abundant number, since it is smaller than the sum of its proper divisors (41363906610240).

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

21171506982048 is an frugal number, since it uses more digits than its factorization.

21171506982048 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26620 (or 26591 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 54.

The spelling of 21171506982048 in words is "twenty-one trillion, one hundred seventy-one billion, five hundred six million, nine hundred eighty-two thousand, forty-eight".