21221331423 has 8 divisors (see below), whose sum is σ = 28362319536. Its totient is φ = 14113948800.

The previous prime is 21221331413. The next prime is 21221331427. The reversal of 21221331423 is 32413312212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21221331423 - 2¹² = 21221327327 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221331393 and 21221331402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221331427) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8399898 + ... + 8402423.

It is an arithmetic number, because the mean of its divisors is an integer number (3545289942).

Almost surely, 2^21221331423 is an apocalyptic number.

21221331423 is a deficient number, since it is larger than the sum of its proper divisors (7140988113).

21221331423 is a wasteful number, since it uses less digits than its factorization.

21221331423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16802745.

The product of its digits is 1728, while the sum is 24.

Adding to 21221331423 its reverse (32413312212), we get a palindrome (53634643635).

The spelling of 21221331423 in words is "twenty-one billion, two hundred twenty-one million, three hundred thirty-one thousand, four hundred twenty-three".