21443230013 has 4 divisors (see below), whose sum is σ = 21444811068. Its totient is φ = 21441648960.

The previous prime is 21443229991. The next prime is 21443230063. The reversal of 21443230013 is 31003234412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17350685284 + 4092544729 = 131722^2 + 63973^2 .

It is a cyclic number.

It is not a de Polignac number, because 21443230013 - 2¹⁸ = 21442967869 is a prime.

It is a super-2 number, since 2×21443230013² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443230063) 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, 770006 + ... + 797367.

It is an arithmetic number, because the mean of its divisors is an integer number (5361202767).

Almost surely, 2^21443230013 is an apocalyptic number.

It is an amenable number.

21443230013 is a deficient number, since it is larger than the sum of its proper divisors (1581055).

21443230013 is a wasteful number, since it uses less digits than its factorization.

21443230013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581054.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21443230013 its reverse (31003234412), we get a palindrome (52446464425).

The spelling of 21443230013 in words is "twenty-one billion, four hundred forty-three million, two hundred thirty thousand, thirteen".