21313444443 has 16 divisors (see below), whose sum is σ = 29227719456. Its totient is φ = 13805164800.

The previous prime is 21313444441. The next prime is 21313444463. The reversal of 21313444443 is 34444431312.

It is not a de Polignac number, because 21313444443 - 2¹ = 21313444441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21313444441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59146 + ... + 214767.

It is an arithmetic number, because the mean of its divisors is an integer number (1826732466).

Almost surely, 2^21313444443 is an apocalyptic number.

21313444443 is a deficient number, since it is larger than the sum of its proper divisors (7914275013).

21313444443 is a wasteful number, since it uses less digits than its factorization.

21313444443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274654.

The product of its digits is 55296, while the sum is 33.

Adding to 21313444443 its reverse (34444431312), we get a palindrome (55757875755).

The spelling of 21313444443 in words is "twenty-one billion, three hundred thirteen million, four hundred forty-four thousand, four hundred forty-three".