21231310223 has 2 divisors, whose sum is σ = 21231310224. Its totient is φ = 21231310222.

The previous prime is 21231310207. The next prime is 21231310249. The reversal of 21231310223 is 32201313212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21231310223 - 2⁴ = 21231310207 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21231310195 and 21231310204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21231310123) 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 as a sum of consecutive naturals, namely, 10615655111 + 10615655112.

It is an arithmetic number, because the mean of its divisors is an integer number (10615655112).

Almost surely, 2^21231310223 is an apocalyptic number.

21231310223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21231310223 is an equidigital number, since it uses as much as digits as its factorization.

21231310223 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21231310223 its reverse (32201313212), we get a palindrome (53432623435).

The spelling of 21231310223 in words is "twenty-one billion, two hundred thirty-one million, three hundred ten thousand, two hundred twenty-three".