21447543243204 has 84 divisors (see below), whose sum is σ = 60602831882796. Its totient is φ = 6599244063168.

The previous prime is 21447543243163. The next prime is 21447543243229. The reversal of 21447543243204 is 40234234574412.

21447543243204 is a `hidden beast` number, since 2 + 1 + 4 + 4 + 7 + 5 + 432 + 4 + 3 + 204 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 10033943169600 + 11413600073604 = 3167640^2 + 3378402^2 .

It is a super-2 number, since 2×21447543243204² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21447543243204.

It is an unprimeable number.

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 27 ways as a sum of consecutive naturals, for example, 282851499 + ... + 282927314.

It is an arithmetic number, because the mean of its divisors is an integer number (721462284319).

Almost surely, 2^{21447543243204} is an apocalyptic number.

It is an amenable number.

21447543243204 is an abundant number, since it is smaller than the sum of its proper divisors (39155288639592).

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

21447543243204 is a wasteful number, since it uses less digits than its factorization.

21447543243204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565778848 (or 565778831 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 45.

The spelling of 21447543243204 in words is "twenty-one trillion, four hundred forty-seven billion, five hundred forty-three million, two hundred forty-three thousand, two hundred four".