21013022243 has 4 divisors (see below), whose sum is σ = 21013317840. Its totient is φ = 21012726648.

The previous prime is 21013022183. The next prime is 21013022273. The reversal of 21013022243 is 34222031012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21013022243 - 2¹⁶ = 21012956707 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013022273) 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, 30653 + ... + 207281.

It is an arithmetic number, because the mean of its divisors is an integer number (5253329460).

Almost surely, 2^21013022243 is an apocalyptic number.

21013022243 is a deficient number, since it is larger than the sum of its proper divisors (295597).

21013022243 is a wasteful number, since it uses less digits than its factorization.

21013022243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295596.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21013022243 its reverse (34222031012), we get a palindrome (55235053255).

The spelling of 21013022243 in words is "twenty-one billion, thirteen million, twenty-two thousand, two hundred forty-three".