21320012233231 has 4 divisors (see below), whose sum is σ = 21337081900000. Its totient is φ = 21302942566464.

The previous prime is 21320012233229. The next prime is 21320012233243. The reversal of 21320012233231 is 13233221002312.

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

It is a cyclic number.

It is not a de Polignac number, because 21320012233231 - 2¹ = 21320012233229 is a prime.

It is a super-2 number, since 2×21320012233231² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21320012233196 and 21320012233205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320012233831) 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, 8534831511 + ... + 8534834008.

It is an arithmetic number, because the mean of its divisors is an integer number (5334270475000).

Almost surely, 2^{21320012233231} is an apocalyptic number.

21320012233231 is a deficient number, since it is larger than the sum of its proper divisors (17069666769).

21320012233231 is a wasteful number, since it uses less digits than its factorization.

21320012233231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17069666768.

The product of its (nonzero) digits is 2592, while the sum is 25.

Adding to 21320012233231 its reverse (13233221002312), we get a palindrome (34553233235543).

The spelling of 21320012233231 in words is "twenty-one trillion, three hundred twenty billion, twelve million, two hundred thirty-three thousand, two hundred thirty-one".