21856956725952 has 224 divisors, whose sum is σ = 66414092175360. Its totient is φ = 7041496734720.

The previous prime is 21856956725897. The next prime is 21856956725969. The reversal of 21856956725952 is 25952765965812.

21856956725952 is a `hidden beast` number, since 2 + 1 + 8 + 5 + 6 + 9 + 567 + 2 + 5 + 9 + 52 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

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 31 ways as a sum of consecutive naturals, for example, 41144143 + ... + 41671985.

Almost surely, 2^{21856956725952} 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 21856956725952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33207046087680).

21856956725952 is an abundant number, since it is smaller than the sum of its proper divisors (44557135449408).

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

21856956725952 is a wasteful number, since it uses less digits than its factorization.

21856956725952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528668 (or 528652 counting only the distinct ones).

The product of its digits is 816480000, while the sum is 72.

The spelling of 21856956725952 in words is "twenty-one trillion, eight hundred fifty-six billion, nine hundred fifty-six million, seven hundred twenty-five thousand, nine hundred fifty-two".