21440021323 has 16 divisors (see below), whose sum is σ = 24632570304. Its totient is φ = 18280120320.

The previous prime is 21440021311. The next prime is 21440021327. The reversal of 21440021323 is 32312004412.

It is not a de Polignac number, because 21440021323 - 2²⁵ = 21406466891 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21440021294 and 21440021303.

It is not an unprimeable number, because it can be changed into a prime (21440021327) 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, 1187403 + ... + 1205323.

It is an arithmetic number, because the mean of its divisors is an integer number (1539535644).

Almost surely, 2^21440021323 is an apocalyptic number.

21440021323 is a deficient number, since it is larger than the sum of its proper divisors (3192548981).

21440021323 is a wasteful number, since it uses less digits than its factorization.

21440021323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18822.

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21440021323 its reverse (32312004412), we get a palindrome (53752025735).

The spelling of 21440021323 in words is "twenty-one billion, four hundred forty million, twenty-one thousand, three hundred twenty-three".