21313220311231 has 2 divisors, whose sum is σ = 21313220311232. Its totient is φ = 21313220311230.

The previous prime is 21313220311199. The next prime is 21313220311247. The reversal of 21313220311231 is 13211302231312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21313220311231 - 2⁵ = 21313220311199 is a prime.

It is a super-2 number, since 2×21313220311231² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21313220311196 and 21313220311205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21313220318231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656610155615 + 10656610155616.

It is an arithmetic number, because the mean of its divisors is an integer number (10656610155616).

Almost surely, 2^{21313220311231} is an apocalyptic number.

21313220311231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21313220311231 is an equidigital number, since it uses as much as digits as its factorization.

21313220311231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 21313220311231 its reverse (13211302231312), we get a palindrome (34524522542543).

The spelling of 21313220311231 in words is "twenty-one trillion, three hundred thirteen billion, two hundred twenty million, three hundred eleven thousand, two hundred thirty-one".