21343121431 has 2 divisors, whose sum is σ = 21343121432. Its totient is φ = 21343121430.

The previous prime is 21343121407. The next prime is 21343121441. The reversal of 21343121431 is 13412134312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21343121431 - 2⁵ = 21343121399 is a prime.

It is a super-2 number, since 2×21343121431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21343121396 and 21343121405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21343121441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671560715 + 10671560716.

It is an arithmetic number, because the mean of its divisors is an integer number (10671560716).

Almost surely, 2^21343121431 is an apocalyptic number.

21343121431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343121431 is an equidigital number, since it uses as much as digits as its factorization.

21343121431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 25.

Adding to 21343121431 its reverse (13412134312), we get a palindrome (34755255743).

The spelling of 21343121431 in words is "twenty-one billion, three hundred forty-three million, one hundred twenty-one thousand, four hundred thirty-one".