21943584563 has 4 divisors (see below), whose sum is σ = 21955703208. Its totient is φ = 21931465920.

The previous prime is 21943584521. The next prime is 21943584589. The reversal of 21943584563 is 36548534912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21943584563 - 2¹⁰ = 21943583539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21943584163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6056606 + ... + 6060227.

It is an arithmetic number, because the mean of its divisors is an integer number (5488925802).

Almost surely, 2^21943584563 is an apocalyptic number.

21943584563 is a deficient number, since it is larger than the sum of its proper divisors (12118645).

21943584563 is a wasteful number, since it uses less digits than its factorization.

21943584563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12118644.

The product of its digits is 3110400, while the sum is 50.

The spelling of 21943584563 in words is "twenty-one billion, nine hundred forty-three million, five hundred eighty-four thousand, five hundred sixty-three".