21847438982721 has 16 divisors (see below), whose sum is σ = 31778595313920. Its totient is φ = 13240662840720.

The previous prime is 21847438982711. The next prime is 21847438982797. The reversal of 21847438982721 is 12728983474812.

It is not a de Polignac number, because 21847438982721 - 2⁵ = 21847438982689 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21847438982711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3099175 + ... + 7300668.

It is an arithmetic number, because the mean of its divisors is an integer number (1986162207120).

Almost surely, 2^{21847438982721} is an apocalyptic number.

It is an amenable number.

21847438982721 is a deficient number, since it is larger than the sum of its proper divisors (9931156331199).

21847438982721 is a wasteful number, since it uses less digits than its factorization.

21847438982721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10463516.

The product of its digits is 86704128, while the sum is 66.

The spelling of 21847438982721 in words is "twenty-one trillion, eight hundred forty-seven billion, four hundred thirty-eight million, nine hundred eighty-two thousand, seven hundred twenty-one".