21055282120872 has 128 divisors (see below), whose sum is σ = 60097751193600. Its totient is φ = 6826956882624.

The previous prime is 21055282120867. The next prime is 21055282120879. The reversal of 21055282120872 is 27802128255012.

21055282120872 is a `hidden beast` number, since 2 + 1 + 0 + 5 + 528 + 21 + 20 + 87 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (21055282120879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4707198 + ... + 8016749.

It is an arithmetic number, because the mean of its divisors is an integer number (469513681200).

Almost surely, 2^{21055282120872} is an apocalyptic number.

It is an amenable number.

21055282120872 is an abundant number, since it is smaller than the sum of its proper divisors (39042469072728).

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

21055282120872 is a wasteful number, since it uses less digits than its factorization.

21055282120872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12724172 (or 12724162 counting only the distinct ones).

The product of its (nonzero) digits is 358400, while the sum is 45.

The spelling of 21055282120872 in words is "twenty-one trillion, fifty-five billion, two hundred eighty-two million, one hundred twenty thousand, eight hundred seventy-two".